Tubulopathies
(1) Renal Fanconi syndrome of proximal tubular dysfunction:
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generalized proximal tubular dysfunction (impaired rabsorption of amino acids,
bicarbonate, glucose, phosphate, urate, sodium, potassium, magnesium, calcium, lowmolecular-weight proteins. Their renal excretion (+ water) is increased, serum
concentration reduced
clinical manifestation: polyuriea, tendency to dehydration, metabolic acidosis
growth retardation and rickets in infancy (vitamin-D resistent rickets –
hypophosphatemia)
1.1. Renal glycosuria.
 autosomal recessive
 low renal threshold for glucose
 urine loss of glucose despite normyl glycemia
1.2. Tyrosinemia type 1
 deficiency in the gene for fumarylacetoacetate hydrolase (chormosom 15)
 cause of neonatal jaundice, failure to thrive, fever, Fanconi syndrome, vomiting,
diarrhea, hepatomegaly, acute liver failure, ascites, coagulopathy….
1.3. Galactosemia¨
 AR disease
 deficiency activity of galactoe-1-phosphate uridyl transferase (mutation at the GALT
gene – chromosome 17)
 increased concentration of galactose in blood and urine
 in neonates vomiting, diarrhea, hypoerbuilirubinemia, ascites, hepatomegaly, E.coli
sepsis a few days after starting milk ingestion
1.4. Cystinosis
 AR disease
 defective lysosomal transport of cystine
 mutation of cystinosis gene CTNS (chormosome 17)
 diagnosis in utero (measurements of cystine in chorionic villi)
 Fanconi sy – failure to thrive, photofobia, rickets
(2) Cystinuria
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increased renal excretion of cystine, ornithine, arginine…
decreased intestinal reabsorption of these AA
renal calculi – resistant to lithotripsy
preventionm – high fluid intake + penicillamine
(3) Renal tubular acidosis
3. 1. Primary proximal renal tubular acidosis
3.2. Distal renal tubular acidosis
(4) Barter syndrome
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congenital chronic tubular disorder
hypokalemic metabolic alkalosis + polyuria + salt wasting + hyperkaliuria +
hyperaldosteronism (? + hypercalciuria + nephrocalcinosis)
increased production of renin
(5) Renal tubular hyperkalemia
causes in neonates:¨
 prematurity
 renal dysplasia
 urinary tract obstruction
 UTI
 pseudohypoaldosteronism,
 congenital adrenal hyperplasia
(6) Congenital nephrogenic diabetes insipidus
causes
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electrolyte abnormality (hypokalemie,a hypocalcemia,
medication (aminoglycosides..)
renal defects (tubular interstitial inflammation, obstrujction, dysplasia)
congenital NDI (X-linked, autosmal recesive)
OR…..
Renal tubular disorders
Primary tubulopathies
Phosphate reasborption (pseudohypoparathyroidism)
Glucose reabsorption (renal glucosuria)
Amino acid reabsorption (classical cystinuria, Hartnup disease)
Bicarbonate reabsorption (proximal tubular acidosis)
Uric acid reabsorption (renal hypouricaemia)
H-ion secretion (distal tubular acidosis)
Electrolyte reabsorption and secretion (pseudohypoaldosteronism, Barter
syndrome, idiopathic hypercalciuria)
Water reabsoroption (nephrogenic diabetes insipidus)
Endocrine tubulofunction (vitamin D-resistant rickets)
Complex tubulofunction (glucosophosphate diabetes, idiopathic renal Fanconi
syndrome)
Secondary (complex) tubulopathies
In inborn effors of metabolism
Galactosemia,
glykogenosis
fruktose intolerance
tyrosinemia
cystinosis
Lowe syndrome
Wilson disease
In acquiered disease
Nephrotic syndrome
Multiple myeloma
Vitamin D deficienty
Hypercalcemia
Hypokalemia
In intoxications
Haevy metals (secondary Fnaconi syndrome)
Drugs
Vitamin D