Finance Subcommittee Update March 17, 2005

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Metro NY/ NJ Pediatric Board

Review Course

Pediatric Fluid/ Electrolytes and

Nephrology

June 2014

Leonard G. Feld MD PhD

Levine Children’s Hospital

Charlotte, NC

Outline

• Fluid and Electrolyte abnormalities

– Dehydration

• Renal

– Hematuria

– Proteinuria

– Hypertension

– Urinary tract infections

– Glomerulonephritis

Case 1

4 mo old infant with 4-5 day history of fever (38.5

o C), numerous watery diarrhea and decreased activity.

Child refused to take breast milk or solid foods.

Mother substituted non-carbonated soda (Coca-cola, etc ~550-700 mOsm/kg H

2

O & < 5 mEq/L Na.

Over last 12 hrs few episodes of emesis and less wet diapers.

EXAM: lethargic, dry mucous membranes, no tears, sunken eyeballs & reduced skin turgor.

BP 74/43 mmHg; Temp 38.5

o C, RR 36 , HR175 beats

WT 6 kg. Weight 7 days ago was 6.6 kg.

There were no other significant findings.

Electrolyte Composition of Body

Fluid Compartments

March 17, 2005

BODY WATER DISTRIBUTION

TOTAL BODY WATER (TBW)

0.6 x Body Weight (BW)

EXTRACELLULAR FLUID

(ECF)

0.2 x BW

Interstitial Fluid Plasma

¾ of ECF ¼ of ECF

INTRACELLULAR FLUID (ICF)

0.4 x BW

Clinical Assessment

Fluid

Deficit

Clinical

Status

Clinical

Assessment

Mild

( 3-5%)

~50 cc/kg Compensated Thirsty,  HR, Normal BP tears, slightly dry mucosa, alert/restless, [urine]

Moderate ~100 cc/kg Decompensated Very dry mucosa, < skin

(6-9%) turgor, sunken eyes, deep resp, weak pulses, cool extremities, oliguria

Severe

(>10%)

>100 cc/kg Shock Intense thirst,  BP, cap refill

> 3 sec, weak pulses, apnea/rapid breathing, coma, anuria

Maintenance Requirements

Body wt 0-10 kg 10-20 kg  20 kg

TBW

Na +

K +

Cl -

100 ml/kg 1000 ml + 1500 +

50 ml/kg for each kg >

10kg

20 ml/kg for each kg >

20kg

3 mEq/kg 3 mEq/kg 3 mEq/kg

2 mEq/kg 2 mEq/kg 2 mEq/kg

5 mEq/kg 5 mEq/kg 5 mEq/kg

Laboratory

Sodium 124 mEq/L

Chloride 94 mEq/L

Potassium 4 mEq/L

Bicarbonate (or total CO2) 12 mEq/L

Serum creatinine 0.8 mg/dL

Blood urea nitrogen 40 mg/dL

Blood glucose 70 mg/dL

Complete blood count was normal except for a hemocrit of 38% (normal ~ 36%)

Hyponatremia

• Serum [Na+] < 130 mEq/L

• Water shifts into cells – lower ECF volume

• <125 mEq/L – nausea and malaise

• < 120 mEq/L – headache, lethargy,

• <115 mEq/L – seizure and coma

Loss of hypertonic Fluid and Sodium from the ECF secondary to Dehydration

NORMAL

0.25 Liters 0.40 Liters

280

280

mOsm/L

35 Na 64 K

0

0

400

Loss

0.10 LIters

AFTER LOSS

0.15 Liters 0.40 Liters

280

10 K

10 Na

200

15 Na

55 K

10 Na

0 0 0

258

AFTER OSMOTIC ADJUSTMENT

0.116 Liters 0.434 Liters

15 Na

54 K

10 Na

0

NORMAL ECF NORMAL ICF

258

0

Question 1: What is the appropriate parenteral solution

A. 5% dextrose + 0.45% isotonic saline +

40 mEq KCl /L

B. 0.45% isotonic saline + 40 mEq KCl /L

C. 0.33% isotonic saline + 40 mEq KCl /L

D. 5% dextrose + 40 mEq KCl /L

E. 5% dextrose + 0.2% isotonic saline

Causes of SIADH

• Neurological conditions

• Pulmonary conditions

• Tumors

• Medications

Criteria

• Hypotonic hyponatremia.

• Inappropriate urine osmolality compared to plasma osm. Patients with medical condition associated with occurrence of SIADH, a urine osmolality > maximal dilution (75-125 mosm/L) and low plasma osm is

“inappropriate” to state of water balance.

• Absence of thyroid, adrenal, cardiac, or renal disease

• Absence of volume contraction

• High urinary sodium concentration

Additional hints for SIADH

• Fluid balance even or positive

• CVP > 6

• Urine volume decreased

• Uric acid decreased

• BUN and Cr decreased

• Urine Na > 20 mEq/L

Points on Hypernatremic Dehydration

NORMAL

0.25 Liters 0.40 Liters

280

280

mOsm/L

35 Na 64 K

0

AFTER LOSS

0.15 Liters

413

0.40 Liters

80

Loss

0.10 LIters

2 K

2 Na

0 0

31 Na

62 K

2 Na

0

280

0

AFTER OSMOTIC ADJUSTMENT

318

0.195 Liters 0.355 Liters

37 Na

62 K

2 Na

0

NORMAL ECF NORMAL ICF

318

0

Hypernatremia – SLOW and CLOSE

Key points: look quiet then irritable on stimulation; may look better than % of dehydration based on weight

Fluid selection: 5% dextrose + ¼ isotonic saline (~30-40 mEq/L of

Na) + 20 mEq KCl /L (D5W with 1/2/ NS + KCl is also OK).

• 1st 24 hrs: 24 hrs of Maintenance + ½ deficit

• 2nd 24 hrs: 24 hrs of Maintenance + ½ deficit

• Close monitoring of serum sodium every 2-3 hours.

Some have suggested using a higher [sodium] – 0.45% isotonic saline or even isotonic saline to restore ECF volume then moving to a lower

• sodium containing solution to restore the water deficit. This approach may also reduce the possibility of dropping the serum sodium too quickly and preventing neurological problems.

Case 2

Susan an 8 yr old noted on routine exam to have moderate hematuria on dipstick.

Unremarkable past medical hx.

Family hx is negative in the parents and siblings for any renal disease. Hx of hematuria is unknown.

Repeat urine in 1 wk still positive, urine culture showed no growth.

Question 2: Which of the following test is the next step in the evaluation?

A. VCUG and urine culture

B. Renal sonogram and urine calcium to creatinine ratio

C. Urology referral

D. CBC and Direct Coombs

E. Recheck in two years

More on Hematuria

• BIG 3

1 Repeat a first AM void following restricted activity , perform a microscopic on a fresh urine

2 Check the family members

3 If there is still blood without protein, casts, crystals, normal BP with or without a strong family history, no further work-up is generally required. However a renal sonogram and urine calcium to creatinine ratio

Glomerular v. Non-glomerular bleeding

• Glomerular

– oliguria, edema, hypertension, proteinuria, anemia

• Non-glomerular – THINK LOWER TRACT

– dysuria, frequency, polyuria, pain or colic, hx exercise

– crystals on microscopic

– mass on exam

– medication history - sulfas, aspirin, diuretics

Initial evaluation of the patient with hematuria

• All patients: BUN, creatinine, kidney and bladder ultrasound, urine calcium to creatinine ratio

• Who should be worked up

– Presence of proteinuria and/or hypertension ,

– History consistent with infectious history, HSP, systemic symptoms, medication use or abuse, strong family history of stones or renal disease/failure.

– Persistent gross hematuria

– Family anxiety - limit evaluation

• Probable glomerular hematuria

– C3, ASO titer

– possible: hepatitis, HIV, SLE serology , SSD

– renal biopsy – not for persistent microscopic without proteinuria, decreased renal function, and/or hypertension

• Probable non-glomeurlar hematuria

– urine culture, urine Ca/creatinine ratio

– possible: hemoglobin electrophoresis,

– coagulation studies, isotope scans,

– Flat plate, CT, ??IVP, cystoscopy

Pearls for Hematuria

• Hematuria may be an important sign of renal or bladder disease

• Proteinuria (as we will discuss) is the more important diagnostic and prognostic finding.

• Hematuria almost never is a cause of anemia

• The vast majority of children with isolated microscopic hematuria do not have a treatable or serious cause for the hematuria, and do not require an extensive evaluation. So a VCUG, cysto and biopsy are not indicated.

More Pearls

• Urethrorrhagia – boys with bloody spots in the underwear

– Presentation – prepuberal ~ 10 yrs

– It is painless

– Almost 50% will resolve in 6 months and > 90% at 1 year; it may persist for 2 yrs

– Treatment – watchful waiting in most cases

• Painful gross hematuria – usually infection, calculi, or urological problems; glomerular causes of hematuria are painless .

More Pearls – gross hematuria

• Gross hematuria is often a presentation of

Wilms’ tumor

• All patients with gross hematuria require an imaging study.

• If a cause of gross hematuria is not evident by history, PE or preliminary studies, the differential includes hypercalciuria or SS trait

• Cysto is rarely helpful

Case 3

7 yr old boy developed gross tea colored hematuria after a sore throat and URI. No urinary symptoms but urine output was decreased. Complained of mild diffuse lower abdominal pain. No fever, rash or joint complaints. Past med hx was unremarkable but had intermittent headaches 2 years ago.

.

EXAM

Afebrile, BP 95/65 mmHg, no edema, some suprapubic tenderness, red tympanic membranes. Mother thinks that a similar episode occur on vacation a few months ago.

Urinalysis - 20 RBCs/hpf, 5-10 WBCs, 100 mg/dL protein, rare cellular and hyaline casts. Serum creatinine is 0.8 mg/dL, C3 100

(normal).

Question 3: The most likely cause of the gross hematuria is:

A. Myoglobinuria

B. Urinary tract infection

C. Obstructive uropathy

D. IgA nephropathy

E. Benign familial hematuria

IgA

• IGA nephropathy

– Boys > girls

– Mostly normotensive, with persistent microscopic hematuria

– Chronic glomerulonephrits – up to 40% of primary glomerulonephritis

– Complement studies are nl, some inc IgA

– Prognosis – not so good if > 10 yrs of age, proteinuria, reduced GFR, hypertension and no macrohematuria

Work of AGN

1. Obtain UA, renal US, 24 hr urine protein/creatinine, spot urine protein and creatinine ratio

2. Glomerulonephritis –active sediment (protein, RBCs, dysmorphic RBCs/or RBC casts), 300 mg - >1 gm/day proteinuria, HTN, edema

3. Low complement GN:

Systemic: SLE, SBE, cryoglobulinemia, shunt nephritis

Isolated renal: post-infectious GN, MPGN

Normal complement GN:

Systemic: HSP, ANCA-associted (Wegener’s, PAN),

Goodpasture’s syndrome, hypersensitivity vasculitis

Isolated renal: IgA nephropathy, anti-GBM disease,

RPGN

Red or Tea colored/ Brown Urine

Fresh Centrifuged Urine Sample

Sediment Red with

Red Cells

Hematuria

NOTE: If there is no red sediment, no RBCs and a clear supernatant, consider other causes such as urates, bile pigments, beets, porphyria, some medications, etc.

Supernatant Red without

Red Cells

Hemoglobinuria

*

Myoglobinuria

* Hemoglobinuria will have a red or pink hue to the serum

Question 4

On routine physical examination, an 8-yearold boy is found to have microscopic hematuria. The first step in your evaluation should be.

A. Examine the urine sediment

B. Order an renal ultrasound

C. Obtain a voiding cystourethrogram

D. Perform a CBC in the office

E. Order an ASO titer and C3

Question 5

An 8-year-old boy presents with tea colored urine. He has very mild edema. History of strep infection about 2 weeks ago. The work-up should include all the following except.

A. Complement studies

B. Serum creatinine

C. Urinalysis for protein

D. Monitor blood pressure and urine output

E. Obtain a renal ultrasound

Acute glomerulonephritis: clinical

• May be clinically asymptomatic (? 90%) with low C3 and hematuria

• Usually within 3 weeks after strep infection

– mean about 10 days

• Periorbital, peripheral edema

• Hematuria - coke-colored, tea-colored, reddish/brown

• Nonspecific findings such as abdominal pain, malaise, anorexia, headaches, pallor

Acute glomerulonephritis: DD

• Acute Poststreptococcal glomerulonephritis

(PSAGN) – most common

• Acute Postinfectious or nonstreptococcal postinfectious glomlerulonephritis 9AIAGN)

– Bacterial: endocarditis (low C3), shunt nephritis (low

C3), pneumococcal pneumonia, etc.

– Viral: hepatitis B, infectious mononucleosis, varicella, etc,

– Parasites:

• Other: SLE (low C3), membranoproliferative GN

(low C3), hyperthyroidism, HSP (nl C3)

Acute glomerulonephritis: evaluation/ treatment

• Evaluation

– ASO, C3, C4

– Renal function

– Evaluation for hypertension and oliguria

– Magnitude of proteinuria

• RX – supportive

– Admission for hypertension, oliguria, impaired renal function, nephrotic syndrome

• Prognosis: C3 normalizes by 12 weeks, hypertension and other abnormalities resolve by

2-3 months, hematuria may persist for 6-24 mo

Proteinuria

Case 6: John is an 12 year old noted on a basketball team physical to have 2+ protein on dipstick. There are no recent illnesses. He has an unremarkable past medical history and he is not taking any medications. Family history is negative in the parents and siblings for any renal disease.

Question 6: Which of the following is the best approach?

A. Obtain a 1 st AM urine for protein

B. Perform a complete biochemical profile

C. Obtain a C3, ASO and ANA

D. Refer for a renal biopsy

E. Schedule a renal sonogram and VCUG

What does Orthostatic Proteinuria mean?

Protein

Excretion

Threshold of Detection

Normal Orthostatic

Recumbant

Erect

More on Proteinuria

• Repeat a first AM void following restricted activity, perform a microscopic on a fresh urine; also an alkaline pH may give a false positive result

• If there is still protein perform a more formal orthostatic test. If orthostatic, no further work-up is generally required, although no indemnification from subsequent renal disease.

Causes of Proteinuria

• Transient

– fever, emotional stress, exercise, extreme cold, abdominal surgery, CHF, infusion of epinephrine

• Orthostatic

– Transient or fixed / reproducible

• Persistent

– Glomerular disease: MCNS, FSGS, MPGN, MN

Systemic: SLE, HSP, SBE, Shunt infections

Interstitial: reflux nephropathy, AIN, hypoplasia, hydronephrosis, PKD

Question 7

A four-year boy presents with a 5-day history of swollen eyes and “larger ankles”. On exam he has periorbital and pretibial edema. The most likely cause of nephrotic syndrome would be?

A. Systemic lupus erythematosus

B. Hemolytic uremic syndrome

C. Minimal change nephrotic syndrome

D. Membranous nephropathy

E. Membranoproliferative glomerulonephritis

Definitions (Pearl)

• Urine protein to creatinine ratio

Normal: < 0.2 (< 0.15 adolescents)

Mild to moderate: 0.2 to 1.0

Heavy or severe: > 1.0

• Persistent proteinuria: present both in the recumbent and the upright posture; even in this situation, proteinuira is less during recumbency

Nephrotic Syndrome

• Primary Nephrotic Syndrome:

– Minimal change disease (~75%) – mean age 4 yrs

• No hematuria, nl C3, no hypertension, nl creatinine

– Membranoproliferative GN (~ 5-10%)

– FSGS (5-10%)

– Proliferative GN, Mesangial proliferation

– Membranous nephropathy

• Secondary Nephrotic Syndrome:

– SLE, HSP, diabetes mellitus, HIV, vasculitis, malignancy

(lymphoma, leukemia), drugs (heroin, inteferon, lithium), infections (toxo, CMV, syphilis, hepatitis B and C)etc.

• Congenital/Infantile Nephrotic Syndrome:

– Finnish-type congenital nephrotic syndrome,Denys-Drash syndrome

– Diffuse mesangial sclerosis, Nail-patella syndrome

Nephrotic Syndrome - RX

Corticosteroid treatment

• Induction therapy: Exclude active infection or other contraindications prior to steroid therapy.

– Oral prednisone- 60 mg/m2/d (~2 mg/kg/d) daily for 4 -6 wks.

– Oral prednisone at 40 mg/m2 (or ~1.5 mg/kg) given as a single dose on alternate days for 4 -6 wks.

• Relapse therapy - For infrequent relapses,

– Prednisone 60 mg/m2/d (~2 mg/kg/d) as single AM dose until proteinuria resolved for at least 3 -4 days.

– Following remission of proteinuria, prednisone reduced to

40 mg/m2 (or ~1.5 mg/kg) given as a single AM dose on alternate days for 4 weeks. Prednisone may then be discontinued or a tapering regimen.

Frequently relapsing nephrotic syndrome is steroid-sensitive nephrotic syndrome with 2 or more relapses within 6 mos or more than 3 relapses within a 12-mo period.

Hypertension

Hypertension

Question 8: David is a 10 year old boy first noted to have an elevated blood pressure of 123/85 during a annual physical examination. Pt has a long history of learning and behavioral issues.

He has a previous history of headaches that were evaluated with a CT scan of the brain and sinuses. On following evaluation in one week, his BP is126/86 mmHg with a weight > 99%ile for age and a height at ~50 th %ile.

Question 8 : What is the most appropriate initial testing for this child?

A. Renal mag-3 flow scan

B. Electrolytes, BUN, Creatinine,

Bicarbonate, glucose

C. Renal Sonogram with doppler

D. Urinary screening for drugs

E. 24 hour urine for catecholamines

BP Classification

Grade of hypertension

Normal

Pre-hypertension

Stage I hypertension

Stage II hypertension

Definition

“White-coat” hypertension BP levels >95th percentile in a physician's office or clinic, but normotensive outside a clinical setting

Appropriate next step

Readings may be obtained at home with appropriate family training or with the assistance of a school nurse, or with the use of ambulatory BP monitoring

(ABPM)

< 90 th %ile

>120/80 mm Hg should be considered pre-hypertensive or

90-95%ile

95 th -99 th %ile + 5 mmHg

Additional readings may be obtained at home with appropriate family training or with the assistance of a school nurse

Organize a diagnostic evaluation in a non-urgent, phased approach

Average SBP or DBP that is >5 mm

Hg higher than the 99 th percentile

Organize a diagnostic evaluation over a short period of time in conjunction with pharmacological treatment

Hypertensive urgency and emergency

Average SBP or DBP that is >5 mm

Hg higher than the 95 th percentile, along with clinical signs or symptoms

Hospitalization and treatment to lower the blood pressure

Estimate of Hypertension

Estimate without height adjustment

1. If systolic BP equals or exceeds

100 + 2 times pt age in yrs

2. If diastolic BP equals or exceeds

70 + pt age in yrs

Estimate with height adjustment

1. If systolic BP at 95 th %tile for age and sex

Add 4 mmHg to the value at the 50th %tile

2. If diastolic BP at 95 th %tile for height

Add 2 mmHg to the value at the 50th %tile

Evaluation of Hypertension

Historical

Information

Physical

Examination

Neonatal history

Family history

Dietary history

Risk Factors (smoking, alcohol use, drug use)

Non-specific / specific symtomatology

Review of Systems - sleep and exercise patterns, etc.

Vital signs

(including extremities)

Height/Weight

Specific attention to organ systems - cardiac, eye, abdominal or other bruits, etc.

Consider ambulatory blood pressure monitor

Evaluation Phase 1

CBC, urinalysis, urine culture, electrolytes, BUN, creatinine, thyroid studies, uric acid plasma renin, lipid profile, echocardiogram, renal ultrasound with duplex doppler

Evaluation Phase 2

Selected studies based on magnitude of the hypertension and/ or other clinical /laboratory findings

Renal flow scan (MAG 3)

CT Angiography (CTA)

MRA (may not provide adequate evaluation for peripheral renal vascular lesions)

Renal arteriography with renal vein sampling

Plasma / urine catecholamines and/or steroid concentrations

Indications for Treatment

• Symptomatic hypertension

• Secondary hypertension

• Hypertensive target-organ damage

• Diabetes (types 1 and 2)

• Persistent hypertension despite nonpharmacologic measures

Pharmacologic Therapy for Childhood Hypertension

• The goal for antihypertensive treatment in children should be reduction of BP to

<95th percentile, unless concurrent conditions are present. In that case, BP should be lowered to <90th percentile.

• Severe, symptomatic hypertension should be treated with intravenous antihypertensive drugs.

Urinary Tract

Infections

Case 9

• A 4 mo old girl presents with low grade fever, mid-lower abdominal pain and nighttime-incontinence. She is not eating well. Prior visits she had normal blood pressure, urinalysis and excellent growth. Urinalysis shows hematuria, 30 mg/dL of protein, leukocyte esterase and positive nitrite. Urine culture is obtained.

53

Question 9:

What is the most likely bacterial cause of her urinary tract infection?

A. Proteus mirabilis

B. E. coli

C. Coagulase positive Staphlococus

D. Alpha hemolytic Streptococcus

E. Klebsiella pneumoniae

Bacteriology /Pathogenesis UTI - 1

• Most Common - E. Coli, coliforms

• Virulence Factors

• adherence to uroepithelium by P-fimbriae

• endotoxin release

• Pyelo vs cystitis - 80 to 20%

55

Bacteriology /Pathogenesis UTI 2

• Perineal / urethral factors

– uncircumcised - 10-20x risk

– ? Urethral caliber (infant girls)

– other myths such as bubble bath, wiping techniques

• Low Urinary factors

– dysfunctional voiding ; constipation

• Other - indwelling catheters, congenital anomalies, Vesicoureteral reflux, sexual activity

56

Diagnosis

• Leukocyte test and nitrite test

• Urine culture > 40-50,000 CFU/mL

• Pyuria - not on recurrent UTIs

57

Clinical Issues

• Lower tract - frequency, urgency, enuresis, dysuria

• Upper tract - fever - nearly all in boys under 1 year of age; females peak in first year but still significant through the first decade

• Asymptomatic bacteriuria - low risk

58

Radiological Evaluation

• Renal ultrasound - anatomy, size, location, echogenicity

• DMSA (2nd choice glucoheptanate -

SGH) cortical integrity, photopenic regions, differential function, abscess

• CT scan - abscess

• VCUG – not the current standard for first

UTI; radionuclide for follow-up or siblings

• IVP - NO WAY

59

AAP SEPT 2011

Practice guidelines

• DX: Urinalysis with pyruria and culture with

50,000 col/ml single organism by SPA or cath

• Treat for 7-14 days

• Ultrasound for all with febrile UTI

• VCUG only with abnl Ultrasound, or other findings to suggest atypical or complex issues

• VCUG – after 2 nd febrile UTI

• No Abx prophylaxis unless VUR grade V

Grades of Reflux

61

Reflux Recommendations

“the simple way”

• GRADES I - III Antibiotics

• GRADES IV - V Surgery

• Although endoscopic approach is gaining favor over open reimplantation

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Treatment

• Oral

– SMX-TMP, Amoxicillin/Clavulanate

– Cefuroxime, cefprozil, cefixime, cefprodoxime

• Parenteral

– Neoates: Ampicillin / Gentamicin

– Older Children:

• Advanced level cephalosporin

• Beta lactam + beta lactamase inhibitor

• Aminoglycoside (+ ampicillin)

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Case10: Case History

• A 12 mo old girl is diagnosed with the first febrile UTI. She is not eating well.

UA shows pyuria and bacteria. Urine culture is obtained and shows >

100,000 colonies of E. Coli. Antibiotics are given.

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Question 10: What is the most appropriate next step?

A. Perform a DMSA renal scan

B. Refer to urology for cystoscopy

C. Perform a renal sonogram

D. Perform urodynamics and flow studies

E. Repeat urine culture in 3 months

Glomerulonephritis / Acute renal failure

Case 11

• 3 year old boy was attending summer camp.

• Five days later he presents with diarrhea, abdominal pain and appear pale.

• His mother finds out that there was cook out at camp.

• EXAM- child is pale & unable to void. LABS

WBC 26,000, hemoglobin 8 g/dL, platelets

98,000, Serum creatinine 1 mg/dL, BUN 54 mg/dL, urinalysis - large blood, 100 mg/dL of protein.

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Question 11: What is the most likely diagnosis?

A. Henoch Schoenlein Purpura

B. Post streptococcal glomerulonephritis

C. IgA nephropathy

D. Acute pyelonephritis

E. Hemolytic uremic syndrome

Clinical prodrome

• Diarrhea prodrome 1-15 days

• Abdominal pain – may be confused with ulcerative colitis, appendicitis, rectal prolapse, intussusception

• Pallor

• Irritability, restlessnes

• Edema – after rehydration

• Oliguria/anuria

HUS: Clinical manifestations

• Thrombocytopenia

• Hemolytic anemia

• Renal failure

• Neurologic (irritability, seizure, CVA)

• Pancreatitis (IDDM) and colitis

• Hypertension

HUS: Pathogenesis

• Endothelial cell damage occurs secondary to toxin injury via binding to glycolipid receptor or lipopolysaccharide absorption.

HUS: Differential diagnosis

• Other forms of acute Glomerulonephritis / renal failure

• Vasculitis

• Urosepsis

• Renal vein thrombosis

• Coagulopathy (DIC)

Conservative management

• Fluid restriction to <insensible losses plus urine output

• Foley catheter – limit to 24-48 hrs

• Blood transfusion / platelets

• Routine use of antibiotics controversial

• Diuretics

• Nutrition

Surgical Complications

• Toxic megacolon

• Rectal prolapse

• Colonic gangrene

• Intussusceptions

• Perforation

• Strictures

• Mimic appendicitis, IBD

BONUS

A 6 year old boy presents with recurrent episodes of brownish urine that developed coincidental with URIs. His urinalysis during the episodes reveals red blood cell casts and small protein. His complement levels are normal. His hepatitis B screen is normal. The MOST likely diagnosis is:

1.Post Strep AGN

2.IgA nephropathy

3.Membranoproliferative glomerulonephritis

4.Membranous nephropathy

5.

Wegener’s granulomatosis

SOME QUICKIES

• Unilateral multicystic dysplastic kidney – MOST COMMOM CAUSE

OF ABDOMINAL MASS IN NEWBORN

– ULTRASOUND AND VCUG to DETERMINE CONTRALATERAL

DISEASE

• Polycystic Kidney Disease

– Autosomal recessive – bilateral enlarged kidneys with microcysts

(Potter’s – pulmonary hypoplasia); overtime – liver fibrosis and failure

– Autosomal dominant – MOST COMMON INHERITED KIDNEY

DISEASE; bilateral enlarged kidneys with MACROCYSTS; association with cerebral aneurysm

• Hydronephrosis

– Usually obstruction; Ultrasound may show enlarged kidney without hydroureter

• Posterior urethral valves –

– MOST COMMON CAUSE of OBSTRUCTIVE UROPATHY IN MALES; remember poor urinary stream and palpable bladder

• Vesicoureteral reflux

– Grades from I to V; VCUG diagnoses REFLUX, Radionuclide (DMSA) scans detect scars ; Surgery for grades IV to V (in general)

• UTIs

– E. coli most common followed by Klebsiella, Proteus. Males over 1 also have E. Coli then Proteus, Staph

– Females > males; greater in uncircumcised; remember constipation may increase incidence of UTIs

– DX – culture, cath or mid stream; UA – positive nitrites and leukocytes

– 1 st febrile UTI – ultrasound ; VUCG for girls with more than 2 UTI in 6 months; all males

• Hematuria

– Rule out hemoglobin and myoglobin

– Brown urine – glomerular – look for red cell casts

– Lower tract – gross red (possible at end of stream), no casts, possible clots

– Rule out hypercalciuria – spot ratio

– Common diseases

• IgA – gross hematuria with respiratory or GI illness

• Post Strep AGN – follows throat or skin infection by 10-21 days,

Low C3 but recovers by 8-12 weeks, maybe increased ASO titer

• HUS – E. coli – 0157:H7 – MOST COMMON CAUSE OF

ACUTE RENAL FAILURE; low platelet count and microangiopathic hemolytic anemia (schistocytes; coombs negative) – cause undercooked meat or unpasteurized milk

• Proteinuria

– Rule out Orthostatic Proteinuria; urine protein to creatinine ratio – abnormal above 0.2 from AM specimen

– Nephrotic syndrome – ratio greater than 2 or more the 40 mg/m2/hr of protein

• Minimal change – steroid responsive is MOST COMMON

• Usually 2- 6 yrs with mean of 4 yrs; remember edema is dependent - first eyes than later in day to the legs.

• Treatment – prednisone – 60 mg/m2/day for 4-6 weeks followed by alternate day steroids for 4-6 weeks.

• Tubular entities

– Diabetes insipidus

• X linked or secondary to ADH resistance

• Look for dilute urine in face of hypernatremia

• Water deprivation test then give IV or intranasal vasopressin

– Renal tubular acidosis – normal anion gap – hyperchloremic metabolic acidosis

• Proximal or Type II – bicarbonate wasting

– Failure to thrive

– pH < 5.5

– Serum bicarbonate usually less than 18

– Remember FANCONI syndrome is RTA = glycosuria, phosphaturia, and amino aciduria.

– Treated with bicarbonate

– Distal or Type I – impaired distal acidification; pH > 5.5; may have hypokalemia and hypercalciuria

– Look for polyuria, vomiting, nephrolithiasis

– Treated with bicarbonate – low dose compared to proximal

– Bartter syndrome

• Hypochloremic metabolic ALKALOSIS; hypokalemia.

• Look for polyuria, failure to thrive, low serum chloride and low potassium

– Kidney Stones

• Imaging of choice – spinal CT.

• Most stones are radiopaque since they contain calcium. Nonradiopaque are uric acid stones.

• Cystinuria – increased urinary excretion of dibasic amino acids

• Acute kidney injury (failure)

– Evaluation to determine – prerenal (perfusion); renal (intrinsic) or post renal (obstruction)

• Chronic kidney disease

– Key items – anemia, growth failure, renal osteodystrophy

– Options – dialysis and preferred renal transplantation

For the Exam

• High frequency sensorineural hearing loss, ocular and renal disease – think Alport syndrome – most cases are X-linked

• Neurofibromatosis – renal abnormality is renal artery stenosis causing hypertension

• Nail patella syndrome – nephrotic syndrome

• Turner syndrome – Horseshoe kidney

• Tuberous sclerosis – angiomyolioma and polycystic kidney, hypertension

• Congenital hepatic fibrosis – autosomal recessive polycystic kidney disease

• Multicystic dysplastic kidney – non-functioning renal tissue check contralateral kidney for abnormalities – may be associated with other conditions such a VATER, CHARGE,

• Mesoblastic nephroma – most common renal mass in neonates

For the Exam

• Hematuria – rarely a cause of anemia; check complements, spot urine calcium to creatinine ratio

• Isolated microscopic hematuria does not require an extensive medical and imaging evaluation.

• Gross hematuria may be a tip for Wilms Tumor and require renal imaging;

– If suspect renal stone – spiral CT is best (sonogram and plain xray may be first test in ED). If pt with a fever and a stone – think

Proteus

– If sickle cell trait or disease need imaging test – ultrasound and possible IVP or CT. Could be papillary necrosis.

• Urethrorrhagia – painless hematuria in males– red blood spots on underwear

• Painful hematuria – stones, infections or other urological disease

For the Exam

• First morning urine is best to assess concentrating ability, exercise induced hematuria and orthostatic proteinuria

• Normal urinary protein is < 0.2 (ratio), < 4 mg/m2/hr; nephrotic

> 40 mg/m2/hr or ratio > 2.

• Fractional excretion of sodium - dehydration < 1; acute renal injury > 2-3

• Hypertension by age

– Newborn and infants – think umbilical catheter, artery or vein thrombosis, coarctation

– Preschool – think renal, renal artery stenosis or coarctation

– School age – think renal renal artery stenosis, essential

– Adolescence – think – essential, obesity, renal or drugs.

For the Exam

• Renal Diseases

– Acute glomerulonephritis: Post strep, low C3 – hospitalization for hyperkalemia, fluid overload or hypertension. C3 resolves by 12 weeks.

– IgA – macroscopic or microscopic hematuria, normal C3

– HSP – normal C3 and platelet count are normal; skin - purpuric papules and may start on lower extremities or other parts of the body including ears, genitalia; GI – may precede rash; intussusception common; renal and joints (arthritis/arthralgias) – they can occur in any order; causes – infections, medications, vaccinations; REMEMBER DIFFENTIAL RENAL DIAGNOSIS includes Post StrepAND FOR PURPURA – Sepsis,

Meningococcemia.

– Membranoproliferative – Low C3 and C4 in Type 1; only C3 low in

Type 2 and 3. Differential is Lupus and Post Strep due to low C3.

Treatment is alternate day corticosteroids

For the Exam

– Nephrotic Syndrome – minimal change; normal C3; steroid responsive in majority of cases; causes – idiopathic, drugs, allergies, tumors (Hodgkin and non-Hodgkin), infections.

Infection potential while on corticosteroids, BEWARE NOT TO

GIVE LIVE VIRAL VACCINES - see REDBOOK

– Focal Segmental Glomerulosclerosis – normal C3; usually a steroid unresponsive form of Nephrotic syndrome; usually idiopathic and an unremarkable (non-nephritic) urinary sediment

(no red cell casts or white cells); can be inherited; usually older patients compared to Minimal change.

– Membranous Nephropathy – older age than minimal change, may be history of hepatitis, unremarkable (non-nephritic) urinary sediment (no red cell casts or white cells); forms of membranous can occur in LUPUS.

For the Exam

• HUS – associated with Shiga Toxin (old term is diarrheal or typical) or S. Pneumoniae infections; can be idiopathic or hereditary; Hemolytic anemia with fragmentation of RBCs, thrombocytopenia and acute kidney failure. Poor prognosis – older age, non-shiga toxin HUS which is often associated with complement mutations

For the Exam

• Polycystic Kidney Disease

– Autosomal recessive – kidney and liver (congenital hepatic fibrosis) – think esophageal varices in later life. Potter’s facies, present in newborn period with large masses; maybe have oliguria, RDS. On ultrasound have increased echogenicity and loss of corticomedullary differentiation. DIFFERENTIAL includes Autosomal dominant, congenital nephrotic syndrome, glomerulocystic disease

– Autosomal dominant – chromosome 16 mutation, may present with hypertension, gross hematuria, or as an incidental finding on ultrasound. MAY have hepatic, pancreatic and genital organ involvement; mitral valve prolapse and cerebral aneurysm

(family association).

• Prenatal ultrasound can detect hydronephrosis, renal agenesis, oligohydramnios and polyhydramnios, cystic kidney disease.

For the Exam

• Nocturnal enuresis

– Recurrence of bed wetting after a period of toilet training – obtain a UA to rule out UTI

– Treatment options for primary enuresis include

• No intervention

• There is progression resolution with age – about

15% each year during school age.

• Alarm have good long term success

• DDAVP is a consideration under special circumstances

ANSWERS TO THE CONTENT

SPECIFICATIONS

• Fluid and electrolyte

• Nephrology

Leonard.feld@carolinashealthcare.org

SUBJECT LINE: NYNJ PEDS

Outline – Part 2

• Acute renal failure

• Chronic renal failure

• More Fluids & Electrolytes

• Tubular disorders

• Cystic kidney disease

SCENARIO

A 6 year boy is diagnosed as having ALL. He is started on chemotherapy and his white blood cell count drops precipitously. The child is discharged and the family is encouraged. However, after two days at home he spikes a temperature to 39

C. The parents contact the heme/ onc fellow who tells them to come to the hospital immediately.

On arrival to the ER, the child is a bit lethargic. His BP is

60/40.

What is the most important first step in the management of this child?

What are the most useful diagnostic tests?

What are the possible causes of his condition?

How should his condition be treated?

Acute Renal Failure (ARF) vs

Pre-renal Azotemia

• Key maneuver is restore RBF to distinguish reversible pre-renal state from short-term irreversible

• Options

– Bolus infusion of crystalloid solutions

– Infusion of albumin

– Administration of pressors

– Administration of antagonists of clinical condition as in anaphylaxis

UA

SG

UNa

FENA

Uosm

ARF: Diagnosis

Pre-renal AGN ATN Obstruction

Marginal value

>1.020

<20

Key

RBC casts

RTEC

>1.020

1.008-

1.012

<20 >40

Marginal value

1.008-1.012

>40

<1%

>400

<1%

>400

>1% >1%

200-400 200-400

ARF: Diagnosis

• AGN

– PSAGN

– HSP

– SLE

– MPGN

– Wegener’s

ARF: Diagnosis

• ATN

– Unreversed pre-renal azotemia

– Nephrotoxic meds

– Contrast agents

– High calcium, uric acid, phosphate

– Rhabdomyolysis (myoglobin)

– Intravascular hemolysis (hemoglobin)

ARF: Diagnosis

• Obstructive uropathy

– PUV

– Prune belly

– Vesicoureteric reflux

– Neurogenic bladder (myelomeningocele)

– Megacystis/megaureter

– Secondary: stones, fibrosis

• Effect of age and gender

ARF: Testing

• Key labs: BUN, creatinine, K

• EKG

• CXRay

• Renal ultrasound

• Specific blood tests based on underlying condition

ARF: Management

• Urgent issues

– Potassium

• Calcium

• Glucose/insulin

• NOT bicarbonate

– Blood pressure: parenteral therapy

• Labetalol

• Nitroprusside

– ECF volume

ARF: Conservative

Management

• Potassium

– Diet restriction

– Kayexalate

• Blood pressure

– IV/PO meds

• ECF volume

– Na restriction

– Diuretic use – need for furosemide

ARF: Indications for Dialysis

• Refractory hyperkalemia

• Refractory hypertension

• Symptomatic ECF volume overload

• Symptomatic azotemia

– Infection

– Bleeding

– CNS changes

ARF: Pearls

• Pre-renal azotemia and AGN are similar

• ATN and post-renal failure are similar

• Potassium kills first in ARF

SCENARIO

A 6 year boy is seen at a routine physical examination.

Although he has no specific complaints, his mother says he has been very listless and his appetite is very poor. He has not been playing well with his friends in play group. Although he is toilet trained he seems to be having more accidents during the night.

On examination, he looks a bit pale and tired. His height has fallen from the 50% at his last visit 18 months ago to 10%. His

BP is 106/62 mm Hg.

What is the most important first step in the diagnosing this child’s problems?

What are the likely causes his condition?

How should his condition be treated?

CKD: Diagnosis

• Stages

– CKD I: renal injury GFR >90

– CKD II: GFR 60-90

– CKD III: GFR 30-60

– CKD IV:GFR 15-30

– CKD V: ESRD

CKD: Common features

• Impact on growth

• Impact on bone: osteodystrophy

• Impact on puberty

• Impact on development – social and cognitive

CKD: Causes

• Non-glomerular

– Hypoplasia/dysplasia

– Reflux nephropathy

– Obstructive uropathy

• PUV

• Prune Belly

• Neurogenic bladder

CKD: Clinical manifestations

• Growth failure

– Dependent on age of onset

– Dependent on level of GFR

• UTIs

– Pyelonephritis

• Electrolyte abnormalities

– Pseudohypoaldosteronism

– Nephrogenic DI

• Neurocognitive disability

CKD: Diagnosis

• Structural assessment

• Imaging studies

– US

– VCUG: dye vs radioisotope

– DMSA scan

– Retrograde studies, etc

CKD: Diagnosis

ARF

Younger child, abd mass, UTI

UA

WBC, impaired concentration

US, VCUG, DMSA

Retrograde studies

Cystoscopy, urodynamics

SCENARIO

A 15 year old girl comes to the clinic because she has not had her period for the last 8 months. She feels tired all the time at home school and is having a hard time concentrating in school.

She is not taking any medications except for occasional

NSAIDs for headaches and some vitamins. Her parents are in good health.

On examination, her height and weight are normal. Her BP is

162/98 mm Hg. She is pale and has a mild amount of edema in both legs. She has no rash or arthritis.

What is the most important first step in diagnosing this adolescent’s problem?

What are the most likely causes?

How should her condition be treated?

CKD: Causes

• Glomerular

– FSGS

– HUS

– SLE

– Membranoproliferative MPGN)

– Alport

– IgA Nephropathy

– Membranous nephropathy

– NOT diabetic or hypertensive nephropathy

CKD: Clinical manifestations

• Growth failure

– Dependent on age of onset

• Hypertension

– Role of 

ECF volume and

PRA

• Electrolyte abnormalities

– Acute

– Hyperkalemia

• Edema

• Signs of underlying disease

CKD: Diagnosis

• Low value of radiology tests

• Blood tests

– C3, C4, CH50

– ASLO

– ANA, dsDNA, Ro, La, Sm

– ANCA

– Anti-GBM

– Renal biopsy

CRF: Management

• Nutritional supplementations

– CHO deficiency

• Protein restriction

– Impact on growth

– Effect in more advanced CKD

• BP control

– Disease progression

– ACEI/ARB

CRF: Management

• Interference with renin-angiotensin aldosterone axis

– Safety of ACEI even with advanced CKD

– Role of combined ACEI/ARB

– Effect of aldosterone antagonists

• Safety issues

– Hyperkalemia

– Reduction in GFR

CRF: Management

• Endocrine treatments

– rhGH

• Doubles growth velocity

• Minimal risk of progression

– Erythropoietin

• Nearly always effective

• Antibody induced pure red cell aplasia

– Calcitriol

• IV route

• More selective agents

CRF: Pearls

• Chronic glomerular diseases have oliguria vs chronic tubular diseases which can have polyuria and sodium loss

– Nocturia and enuresis may indicate CRF

• Severity of growth failure and neurocognitive deficits are inversely related to age of onset of CRF

CRF: More pearls

• Most important feature of nutritional support is to correct low caloric intake

• Medication doses need to be adjusted as

GFR declines

• Almost no form of CRF is a contraindication to transplant

SCENARIO

A 10-day male infant presents with a history of irritability, low grade fever, emesis and diarrhea. Prenatal and family history is non-contributory. On examination the infant is irritable, temp is 38 °C, has mottled skin and a capillary refill of 4 sec. The systolic blood pressure is barely palpable and the pulse is 195 beats/min. The anterior fontanelle is flat.

Hemoglobin

White cell count

Platelets

18 g/dl

30,000

280,000

What are key features in the history and examination?

What studies would you perform?

What is your initial therapy?

What is your initial diagnosis (es)?

Electrolyte Disorders: Sodium

• KEY function of Na+

– ECF cation

– Maintenance of intravascular compartment

• Disturbances in ECF volume are secondary to disturbances in Na+ balance

• ECF volume assessment is clinical

– Reduced – see dehydration above

– Increased – pulmonary and/or peripheral edema

March 17, 2005

Electrolyte disorders: Sodium

Assess ECF

Measure serum Na

High ECF Normal ECF Low ECF

Electrolyte Disorders: Sodium

• History

• Source of Na loss

• Change in body weight

• Renal response to low ECGF volume

– Oliguria

– Reduced urine Na+

– Reduced FENA

March 17, 2005

120

100

80

60

40

20

0

Electrolyte disorders: Sodium

ICF

ECF

Normal Hypo Hyper

Electrolyte disorders: Sodium

• Hypernatremia

– Risk factors

• Breast feeding

• Feeding errors

• Impaired thirst

• Impaired access to water

– Presentation

• Irritability, seizures

– Treatment

• SLOW

• HYPOTONIC FLUIDS – 1/5 NS

Electrolyte disorders: Sodium

• Hyponatremia

– Risk factors

• Feeding errors (Keating)

• Salmonella diarrhea

• Increased extra-renal salt loss

• Pain, anesthesia, post-operative picture

• Female gender

– Presentation

• Lethargy, seizures

– Treatment

• ?SLOW

• Correction 

25 mmol/L OR

130 mmol/L over initial 48 hr

Electrolyte disorders: Sodium

• Bad outcomes

• Brain

– Hemorrhage and cerebral edema in hypernatremia

– Osmotic demyelinating syndrome and acute CNS deterioration in Hyponatremia

• DKA

– ?Hyponatremia ( 

100 glucose mg/dl

 

1.6 Na meq/l)

– Comparison to hypernatremia

SCENARIO

A 4-week old infant presents with a history of irritability, low grade fever and poor feeding. Prenatal and family history is non-contributory. On examination the infant is irritable, temp is 37 °C, has dark skin and a capillary refill of 4 sec.

The systolic blood pressure is barely palpable and the pulse is 195 beats/min. The anterior fontanelle is sunken.

Hemoglobin

White cell count

Platelets

18 g/dl

30,000

280,000

What are key features in the history and examination?

What studies would you perform?

What is your initial therapy?

What is your initial diagnosis (es)?

Electrolyte Disorders: Potassium

• KEY function of K+

– ICF cation

– Transmembrane potential, secretion, neuromechanical coupling

• Disturbances in K+ reflect sudden changes in serum concentration and transmembrane ratio

• Assessment is linked to cardiac impact of abnormal K+ concentration

Electrolyte disorders: Potassium

• Regulatory organs

– Kidney secretion

• Na+

• Urine flow rate

– Adrenal

• Aldosterone

– GI tract

• Transmembrane

– pH

– Osmolality

– Beta adrenergics

– Insulin

• Diet

Potassium

• Key tests

– BUN, Cr, Na, K, bicarbonate

– Urine K useless

– Urine Na/K ratio

– Hormones

• PRA

• Aldosterone

Electrolyte disorders: Potassium

• Hyperkalemia

– EKG

• Peaked T waves

– Treatment

• Calcium infusion

• Glucose/insulin

• NOT Bicarbonate

• Kayexalate

• DIALYSIS

Hyperkalemia: differential diagnosis

• No real disease

– Increase cells: WBC, polycythemia, thrombocytosis, crush injury

– Transmembrane

• Renal

– ARF

– CRF

– Liddle’s

• Adrenal

– Adrenal failure

– Congenital adrenal hyperplasia – ambiguous genitalia

– Isolated renin abnormalities

Hyperkalemia: Work-up

• BUN, creatinine, Na, K, Bicarbonate

• PRA

• Aldosterone

• Urinary Na/K ratio

Electrolyte disorders: Potassium

• Hypokalemia

– EKG

• U waves

– Treatment

• Restore ECF volume to 

2

 hyperaldosteronism

• PO potassium

– Limitations: tolerance

• IV potassium

– Limitation: 0.3 meq/kg/hr

– Central vs peripheral IV

Hyperkalemia: differential diagnosis

• Systemic

– Malnutrition

• Adrenal

– Adrenal overactivity

– Congenital adrenal hyperplasia

– Primary renin abnormalities

• Renal

– DKA

– Osmotic diuresis

SCENARIO

A 15 month child presents with a history of poor feeding and impaired growth. Prenatal and family history is noncontributory. On examination the infant’s height and weight are below the 5 th percentile. The systolic blood pressure is 102 and the pulse is 110. The rest of the examination is normal.

Na

Cl

138

114

Bicarbonate 16

What are key features in the history and examination?

What studies would you perform?

What is your initial therapy?

What is your initial diagnosis (es)?

Electrolyte disorders: acid-base

Acid load

Acute

Lung

Chronic-Kidney

Proximal

Chronic-Kidney

Distal

Reclaim filtered bicarbonate

Regenerate

Titrated bicarbonate

Large frequent doses

1-3 mmol/kg/day

Electrolyte disorders

• Anion gap

• [Na] – {[Cl] + [HCO3]}

• Normal value: 4-12

• Impact of serum albumin

March 17, 2005

Electrolyte disturbances: RTA

• Metabolic acidosis

– Normal anion gap -- hyperchloremic

• Diarrhea

• RTA

– High anion gap -- normochloremic

• MUDPIES or KUSSMAUL

• Key entities:

– DKA

– Lactic acidosis

– Uremia

– Metabolic disease

– Toxins

Electrolyte disturbances: RTA

• Proximal

– Low K

– Primary

– Secondary

• Glycogen storage

• Wilson’s, fructose intolerance, tyrosinemia

• 

PTH,

Vitamin D

• Cystinosis

Electrolyte disturbances: RTA

• Distal

– Primary

– Secondary

• Transplant rejection

• Drugs: amphotericin, cisplatinum

• Collagen vascular disease

Electrolyte disorders: RTA

• Assessment

– SMAC: Cl-

– VBG: Bicarbonate

– Urine: calcium, citrate

– Urine anion gap: unmeasured cation (NH4+)

– Xrays

Electrolyte disturbances: RTA

• Treatment

• Proximal

– Higher doses of bicarbonate

– More frequent dosing

– Exacerbation of hypokalemia with Rx

• Distal

– 1-3 mmol/kg varying with age and diet

– 3 doses

– Stabilization of K with Rx

Electrolyte disorders: Fanconi’s

Fanconi’s

Syndrome

Complete proximal tubule dysfunction

RTA Glycosuria

Phosphaturia

TRP

Amino

Aciduria

Electrolyte disorders: metabolic alkalosis

• Extrarenal/GI loss of K

– CF

• Vomiting

– NG suction

– Pyloric stenosis

• Distal GI loss of bicarbonate

– Chloride diarrhea

• Renal

– Bartter’s

– Gitelman’s

– Apparent mineralocorticoid excess (AME)/licorice

Electrolyte disorders: DI

• Central

• Nephrogenic

• Risk of CNS disease

– 1/12 (1/3 X ¼) of loss from ECF

– Limited access to water

– Altered thirst

Electrolyte disorders: DI

• Central

– AVP replacement

• Nephrogenic

– Adequate water intake

– Low solute diet

– Hydrochlorothiazide

Electrolytes: Pearls

There are three pure renal causes of FTT – azotemia, DI, and RTA

RTA causes hyperchloremic acidosis

Bartter’s and Gitelman’s differ in calcium excretion – high in former low in latter

Thank you

GOOD LUCK

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