Case Studies
Received 2.5.06 | Revisions Received 2.15.06 | Accepted 2.15.06
Jaundice and Cola-Colored Urine in a Young
Indian Boy
Anureet Kaur, MBBS,1 Menka Doomra, MD,1 Naveen Kakkar, MD,1 Jasbir Dhanoa, MD2
(Departments of 1Pathology and 2Medicine, Christian Medical College and Hospital, Ludhiana, Punjab, India)
DOI: 10.1309/2AQ5LAYPQ82RHD3P
Clinical History
Patient
16-year-old Indian boy.
Chief Complaint
Fever, jaundice, and passage of cola-colored
urine for 1 day. The patient was admitted to the
hospital for follow-up.
Physical Exam Findings
The patient was well built and had severe pallor
and icterus. There was no organomegaly.
Drug History
Intake of an unbranded white powder given by
a non-licensed individual.
2. The constellation of this patient’s clinical and laboratory
findings (eg, markedly decreased hemoglobin and hematocrit
levels with a markedly increased serum LD activity), along with
the history of intake of an unknown drug and the presence of
bite/blister cells and microspherocytes in the PBS, are characteristic of acute oxidant damage to the red blood cells and hemolysis
due to glucose-6-phosphate dehydrogenase (G6PD) deficiency.
3. Most likely diagnosis: acute hemolysis due to G6PD deficiency. Deficiency of G6PD is the most common metabolic disorder of red blood cells.
Table 1_Principal Laboratory Findings
Test
Hematology
WBC count
Hemoglobin
Hematocrit
Platelet count
Reticulocyte count
Corrected reticulocyte count
Differential: Myelocytes
Metamyelocytes
Neutrophils
Lymphocytes
Eosinophils
NRBCs
PBS findings
Chemistry
BUN
Creatinine
Bilirubin, total
Bilirubin, direct
ALT
AST
ALP
LD
Patient’s Result
Reference Range
28.3
4.0-11.0 x 103/µL
3.5
12.0-16.0 g/dL
11.4
38-47%
211
150-400 x 103/µL
50.0
0.2-2%
12.6
–
10
0%
11
0%
71
40-80%
7
20-40%
1
0-6%
5/100 WBCs
Anisopoikilocytosis with numerous microspherocytes, bite and blister cells, irregularly
contracted cells, few macrocytes and nucleated and polychromatic RBCs; some of the
RBCs showed basophilic stippling and
Howell-Jolly bodies [Image 1]
139
2.0
12.9
1.0
29
244
97
5165
15-45 mg/dL
0.7-1.5 mg/dL
0.5-1.4 mg/dL
0-0.4 mg/dL
5-50 U/L
5-50 U/L
70-230 U/L
230-460 U/L
WBC, white blood cell; NRBCs, nucleated red blood cells; PBS, peripheral blood smear;
BUN, blood urea nitrogen; ALT, alanine aminotransferase; AST, aspartate aminotransferase;
ALP, alkaline phosphatase; LD, lactate dehydrogenase.
4. The incidence of the deficiency state varies from 20%
among African Bantu males to 12% in African-American men
and 8% in Brazilian blacks. G6PD deficiency is also prevalent
among the Greek population with a maximum incidence of
20% to 32% in the low lands. In Cambodia, South China, and
India, the incidence is 14.0%, 5.5%, and 2.6%, respectively. It is
rare among native Americans.
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Possible Answers
1. Fever, abdominal pain, passage of cola-colored urine,
pallor, icterus, severe anemia, leukocytosis, azotemia,
hyperbilirubinemia, markedly increased lactate dehydrogenase
(LD), and the presence of microspherocytes, bite/blister cells
with polychromasia, and nucleated red blood cells in the peripheral blood smear (PBS) (Table 1 and Image 1).
LABMEDICINE 䊏 Volume 37 Number 7 䊏 July 2006
Hospital Course
The patient’s hematological findings reverted
back to normal within 10 days of hospitalization
although he developed renal failure consequent
to massive hemolysis.
Medical/Family History
Unremarkable.
Questions
1. What is (are) this patient’s most striking clinical and
laboratory findings?
2. How do you explain these findings?
3. What is this patient’s most likely diagnosis?
4. What is the geographical distribution of this condition?
5. What is the inheritance pattern and the subtypes of this
condition?
6. What is the pathogenesis of the condition leading to
hemolysis in this patient?
7. What are the principal clinical features of this patient’s
condition?
8. What are the factors which predispose an individual to the
clinical manifestations associated with this patient’s
condition?
9. What are the laboratory investigations which can be carried
out to diagnose this patient’s condition?
10. What are the other red cell enzymopathies which have
hematological manifestations?
422
Principal Laboratory Findings
Table 1 and Image 1
Case Studies
5. G6PD deficiency is a sex-linked trait with the gene for
G6PD located on the X-chromosome (band Xq28). It is
expressed in males carrying the variant of the gene, whereas heterozygous females are usually clinically normal. Because of inactivation of one of the 2 X-chromosomes (Lyon hypothesis),
heterozygotes have 2 populations of RBCs—normal and G6PD
deficient. The degree of lyonisation and the degree to which the
abnormal G6PD variant is expressed decide the enzyme activity
in females, which may be normal, moderately reduced, or
grossly deficient. More than 400 biochemical variant forms of
G6PD are recognized. The normal G6PD enzyme is designated
as type G6PD B. The most common variant is G6PD A—encountered primarily in individuals of central African descent.
This is followed by G6PD Mediterranean in prevalence. The
other commonly occurring variants are G6PD A+ and G6PD
Canton. The names for the newer variants are designated
according to the location of the individual in whom they were
first described.
7. The common clinical features of G6PD deficiency are
acute hemolytic anemia, favism, congenital non-spherocytic hemolytic anemia, and neonatal hyperbilirubinemia. Acute
hemolytic anemia occurs only after exposure to certain offending agents (drugs, infections, acidosis). After 2 to 4 days of exposure to the offending agent, all signs and symptoms of acute
hemolytic anemia are observed which include jaundice, pallor,
and dark colored urine, with or without abdominal and back
pain. There is an abrupt decrease of 3 to 4 g/dL in hemoglobin
concentration. The anemia is self-limited because the older susceptible population of RBCs is replaced by younger RBCs with
sufficient G6PD activity. A similar clinical presentation occurs in
favism on ingestion of fresh fava beans (Vicia fava; European
broad bean) or inhalation of pollen from the fava plant. In congenital nonspherocytic hemolytic anemia, anemia, jaundice,
and hyperbilirubinemia occur, along with hemolysis in the absence of a triggering factor. Beyond infancy, signs and symptoms
of G6PD deficiency are subtle, and mild to moderate anemia is
the rule. Neonatal hyperbilirubinemia occurs due to ingestion
of drugs, chemicals, and/or fava beans by mothers in late gestation leading to accelerated RBC destruction or impaired liver
clearance of bilirubin.
8. Hemolytic crisis occurs only after exposure to certain
offending agents, including drugs, infections, exposure to fava
beans, and diabetic acidosis. Drugs associated with hemolysis in
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9. The diagnosis of G6PD deficiency can be made by indirect or direct methods. Indirect methods include hematological
and biochemical changes. Hematological changes include a fall
in hemoglobin concentration by 4 to 8 g/dL and marked
anisopoikilocytosis following an acute hemolytic episode. The
peripheral blood smear shows microspherocytes, irregularly contracted cells, and eccentrocytes (blister or bite cells). Blister cells
are red blood cells in which the hemoglobin appears to be drawn
to one side of the cell, leaving an unstained non-hemoglobin
containing cell membrane. (Image 1). Also seen are red cell fragments, polychromatic RBCs, and basophilic stippling. There is
associated moderate leukocytosis and thrombocytosis. Reticulocytosis occurs within 5 days. Heinz bodies can be demonstrated
by supravital staining early in the hemolytic episode. Biochemical changes that provide indirect evidence of hemolysis in G6PD
deficiency include hyperbilirubinemia, raised plasma hemoglobin, markedly elevated serum lactate dehydrogenase (LD) activity, low serum haptoglobin level, and positive tests for urine
hemoglobin and hemosiderin. Direct methods involve demonstration of deficient or reduced activity of G6PD. It is important
that this testing is not carried out during an acute hemolytic
episode as reticulocytosis can give rise to a false negative result,
the younger RBCs being rich in G6PD. Accurate estimation of
G6PD deficiency is possible if testing is carried out 2 to 3
months following an acute hemolytic episode when reticulocytosis has subsided and steady state hematopoiesis has been
restored. The majority of these screening tests demonstrate the
presence or absence of G6PD by the ability of the red cells to
generate NADPH from NADP with simultaneous oxidation of
Image 1_Patient’s peripheral blood smear showing microspherocytes, bite/blister cells (arrows) with hemoglobin drawn to one side
of the RBC, irregularly contracted cells, and a polychromatic RBC
(arrowhead). A nucleated red blood cell is also present along with a
neutrophil. (Leishman stain; 1,000x magnification).
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6. G6PD is an enzyme of the hexose monophosphate
(HMP) shunt pathway, which metabolizes 5% to 10% of the
glucose used by RBCs. It catalyzes oxidation of glucose-6-phosphate (G6P) to 6-phosphogluconolactone with simultaneous
reduction of nicotinamide adenine dinucleotide phosphate
(NADP) to reduced NADP (NADPH). The latter is an important reducing compound for conversion of oxidized glutathione
(GSSG) to glutathione (GSH) which protects red cells against
free radical (eg, superoxide anion) oxidative injury. Individuals
with G6PD deficiency, especially when exposed to certain drugs,
are unable to maintain adequate levels of reduced glutathione in
their RBCs leading to oxidation of hemoglobin sulfhydryl
groups. Hemoglobin precipitates within RBCs, forming Heinz
bodies. These membrane-bound inclusions lead to mechanical
trapping of affected red cells in splenic capillaries resulting in
hemolysis. Both intravascular and extravascular hemolysis occurs
in these patients.
G6PD deficiency include antimalarials (Primaquine,
pamaquine), sulphonamides (Sulphamethoxazole), nitrofurantoin, analgesics (acetaminophen, aspirin, phenacetin), isoniazid
(INH), methylene blue, and nalidixic acid. G6PD deficiency
due to accidental exposure of children to naphthalene (present in
moth balls) has also been reported. The common infectious
agents which trigger hemolysis in G6PD deficient individuals
are Salmonella, E. coli, β-hemolytic streptococci, and Rickettsiae.1,2
Case Studies
an appropriate substrate. The laboratory techniques used to
demonstrate G6PD deficiency include the brilliant cresyl blue
dye test, methemoglobin reduction test, and the fluorescent spot
test.3 An enzyme assay which spectrophotometrically measures
the rate of reduction of NADP to NADPH is also available.
Common deficient G6PD variants can also be diagnosed by
restriction enzyme digestion of the appropriate PCR product.4
More recently, denaturing high performance liquid chromatography (DHPLC) has been used for rapid detection of G6PD
mutations.5
10. Other red cell enzymopathies which have hematological
manifestations include those associated with enzymes of the Embden-Meyerhof pathway (pyruvate kinase, hexokinase, phosphofructokinase, phosphoglycerate kinase and aldolase), enzymes
involved in nucleotide metabolism (adenylate kinase deficiency,
pyrimidine 5-nucleotidase), and other enzymes of the HMP
shunt pathway (glutathione reductase, glutathione synthetase). LM
Keywords: G6PD, lyonisation, hemolysis, anisopoikilocytosis,
blister cell, glutathione
1. Frank JE. Diagnosis and management of G6PD deficiency. Am Fam Physician.
2005;72:1277-1282.
2. Glader B. Hereditary hemolytic anemias due to enzyme deficiencies. In: Greer
JP, Foerester J, Lukens JN, Rodgers GM, Paraskevas F, Glader B, editors.
Wintrobe’s Clinical Hematology, 11th ed. Philadelphia: Lippincott Williams and
Wilkins; 2004: 1115-1140.
3. Jiang J, Ma X, Song C, et al. Using the fluorescence spot test for neonatal
screening of G6PD deficiency. Southeast Asian J Trop Med Public Health.
2003;34S:140-142.
4. Al-Ali AK, Al-Mustafa ZH, Al-Madan M, et al. Molecular characterization of
glucose-6-phosphate dehydrogenase deficiency in the Eastern Province of Saudi
Arabia. Clin Chem Lab Med. 2002;40:814-816.
5. Tseng CP, Huang CL, Chong KY, et al. Rapid detection of glucose-6phosphate dehydrogenase gene mutations by denaturing high-performance
liquid chromatography. Clin Biochem. 2005;38:973-980.
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