Lysinuric Protein Intolerance

Autosomal recessive disease characterized by defective transport of the dibasic amino acids. Failure to thrive, poor growth during childhood, hepatomegaly, splenomegaly, sparse hair, and muscle hypotonia. Normal development to moderate mental retardation.

Hyperdibasic Aminoaciduria type II.

The highest known incidence is observed in Finland with 1:60,000 live births. Other areas with a high incidence are Japan, Italy, and Turkey; however, only approximately 100 patients have been described in the literature.

Transmission is autosomal recessive, with the defect linked to chromosome 14q11.2.

Caused by a defect in the renal and intestinal transport system for lysine and for ornithine and arginine (dibasic amino acid transport). In contrast to patients with cystinuria, these patients do not have increased urinary cystine excretion.

Symptoms can become apparent any time after birth, although breast-feeding seems to delay the onset (probably because of its low-protein content). However, as soon as these patients receive nutrition with a higher protein content, hyperammonemia, diarrhea, nausea, vomiting, and even coma may occur. If undiagnosed, additional clinical symptoms, including failure to thrive as a consequence of the episodes of diarrhea and vomiting, mild-to-moderate hepatosplenomegaly, osteoporosis, and sparse scalp hair, may develop. Hyperammonemia is usually present only after protein feeding, which is thought to be the result of a disturbance in the urea cycle secondary to decreased levels of arginine and ornithine. Mild-to-severe anemia has been reported in some of these patients who are on a low-protein diet with citrulline replacement. Osteoporosis is often severe and in childhood results in fractures after only minor trauma. Glomerulosclerosis and chronic interstitial lung disease are not uncommon. A potential fatal complication in these patients is an interstitial pneumonia with alveolar proteinosis. The cause for complication is unknown. Intermittent hemophagocytotic lymphohistiocytosis with increased levels of ferritin and lactate dehydrogenase and an association with systemic lupus erythematosus have been reported to be a regular feature of this syndrome. l-Arginine deficiency was also responsible for vascular endothelial dysfunction via a decrease in nitric oxide production, which became normal after an l-arginine infusion. In another report, the l-arginine deficiency was found to be responsible for thrombocytopenia and increased antithrombin III levels, which normalized after an l-arginine infusion or transdermal nitroglycerin application. Mental development is usually normal, although frequent and long-lasting episodes of hyperammonemia are considered deleterious for the brain, and amazing recoveries have been reported under strict diet.

An anesthesiology consultation is highly recommended before elective surgical procedures. Proper evaluation of intravascular volemia, electrolyte imbalance, and feeding habits. The patient should be admitted the day before surgery to allow proper fluid resuscitation and electrolyte correction. Obtain a coagulation profile and bleeding time; if abnormal, correct immediately. Anemia is often present and requires correction. In the presence of moderate-to-severe hyperammonemia, elective surgery should be delayed until proper correction, to avoid neurologic deficit.

No reports about anesthesia in these patients were found. Obtain a complete cell blood count, clotting screen, electrolytes, BUN, and creatinine, as well as pulmonary, liver, and kidney function tests. Depending on the severity of the interstitial lung disease and the planned procedure, the need for postoperative mechanical ventilation support should be anticipated. Be cautious if the patient is on total parental nutrition; it must be maintained or replaced by properly adjusted glucose fluid administrations. Careful positioning is required to prevent fractures in the presence of severe osteoporosis. Immunologic problems have been reported in some of these patients; consequently, a strict aseptic technique is recommended.

No known specific pharmacological implication to anesthetic agents.

Blue Diaper Syndrome: Genetic disorder with defective transport for l-tryptophan resulting in blue urine. It is characterized by the presence of hypercalcemia and nephrocalcinosis. Bacterial degradation of the tryptophan leads to excessive indole production and to indicanuria that, on oxidation to indigo blue, causes a peculiar bluish discoloration of the diaper. Although almost certainly recessive, the disorder could be X-linked. It has also been suggested that it results from blue-green discoloration of the stools by a pigment elaborated by Pseudomonas aeruginosa.

Hartnup Disease: Autosomal recessive disorder caused by a defective transport of tryptophan and other neutral (i.e., monoamino-monocarboxylic) amino acids in the small intestine and kidney. Patients may present with a pellagra-like skin condition, cerebellar ataxia, and gross aminoaciduria.

Diaminopentanuria: Increased renal clearance of cystine, lysine, arginine, and ornithine as a result of 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 intestine.

Hyperprolinemia: Autosomal recessive inherited disorder with decreased renal tubular reabsorption of glycine and the amino acids proline and hydroxyproline. Patients with type II of the disease may be taking antiseizure medication, so epileptogenic drugs should be avoided.