Genetic disorder with defective transport for
L-tryptophan resulting in blue urine.
Familial Hypercalcemia and Indicanuria; Drummond
Syndrome; Familial Hypercalcemia with Nephrocalcinosis and Indicanuria;
Tryptophan Malabsorption Syndrome.
Very rare with a frequency of 1:1117 consecutive
patients studied for detection of inborn error of metabolism.
Either autosomal recessive or X-linked
Caused by a deficiency of a substrate-specific
intestinal membrane transport system for L-tryptophan. The defect is located
in the brush-border membrane of epithelial cells in the small intestine and
kidney tubules, similar to Hartnup disease, cystinuria, iminoglycinuria, and
lysine malabsorption syndrome.
Blue discoloration of the diapers starting in early
infancy is secondary to bacterial degradation of tryptophan, producing
indigo blue by enzymatic conversion of indolic compounds in the urine.
Severe and prolonged hypercalcemia is frequent. Excess tryptophan is
measured in the feces of the child, and increased tryptophan derivatives
(indole acetic acid, indole lactic acid) found in the urine are of
intestinal origin. These derivatives result from an increased concentration
of tryptophan in the intestinal lumen. The plasma concentration of
tryptophan is normal, but the increase following oral l-tryptophan
intake is less than normal. Renal clearance of tryptophan is normal. In one
report, the blue-greenish stool discoloration was attributed to a pigment
derived from Pseudomonas aeruginosa.
Hypercalcemia and nephrocalcinosis are associated
with failure to thrive, recurrent unexplained fever, infection,
irritability, and constipation. Prognosis is unfavorable if complicated by
nephrocalcinosis. Ocular abnormalities, such as microcornea, hypoplasia of
the optic disc, and abnormal eye movements, have been described. The
indoluria may look like the one in Hartnup syndrome, but a specific
Evaluation of hydration, renal
function, and hypercalcemia. Treatment of potentially associated infections.
Rule out paralytic ileus.
A case of perioperative death has been
reported after a mastoidectomy in an infant, but no data on the anesthetic
technique used are available. Regional anesthesia can be performed. Because
of a tendency toward dehydration, anesthetic drugs that may mask a low
circulating volume and lead to vascular collapse should be avoided.
Appropriate hydration and urinary output must be enforced. Paralytic ileus
results in increased risk of regurgitation and aspiration during induction.
Consequently, a rapid sequence induction is mandatory.
Avoid drugs with predominantly renal elimination
(or consider reduced dose) in the presence of decreased kidney function.
Hartnup Disease: Autosomal recessive disorder caused by a
defective transport of tryptophan and other neutral (i.e.,
monoamine-monocarboxylic) amino acids in the small intestine and kidneys.
Patients may present with a pellagra-like skin condition, cerebellar ataxia,
and gross aminoaciduria.
Diaminopentanuria: Increased renal clearance of cystine, lysine,
arginine, and ornithine secondary to a dysfunction of the reabsorptive
capacity of the renal tubules. In addition, defective intestinal absorption
results in increased degradation of these amino acids by bacteria in the
Hyperprolinemia: Autosomal ...