Icterus (Chronic Familial)

Introduction

Icterus, also known as jaundice, is a condition characterized by a yellowish discoloration of the skin, whites of the eyes, and mucous membranes. It occurs when there is a buildup of bilirubin, a yellow pigment produced by the breakdown of heme, the iron-containing component of hemoglobin.

Chronic familial icterus is a rare inherited disorder that causes persistent jaundice from birth. It is caused by a deficiency of an enzyme called UDP-glucuronosyltransferase (UGT), which is responsible for converting bilirubin into a water-soluble form that can be excreted in bile.

Causes

Chronic familial icterus is caused by mutations in the UGT1A1 gene, which encodes the UGT enzyme. These mutations result in a deficiency or complete absence of UGT activity, leading to an accumulation of bilirubin in the body.

Inheritance

Chronic familial icterus is an autosomal recessive disorder, meaning that both parents must carry the mutated gene in order for a child to inherit the condition. If only one parent carries the mutated gene, the child will be a carrier but will not have symptoms of the disorder.

Symptoms

The main symptom of chronic familial icterus is persistent jaundice, which is present from birth. The yellow discoloration may vary in intensity, depending on the severity of the enzyme deficiency. Other symptoms may include:

• Dark urine
• Light-colored stools
• Itching (pruritus)
• Fatigue
• Abdominal pain

In severe cases, chronic familial icterus can lead to liver damage and cirrhosis.

Diagnosis

Chronic familial icterus is diagnosed based on a combination of clinical symptoms, physical examination, and laboratory tests.

Physical examination: The doctor will examine the skin, eyes, and mucous membranes for jaundice. Laboratory tests: Blood tests will be performed to measure bilirubin levels and assess liver function. Genetic testing can be used to confirm the diagnosis.

Treatment

There is no cure for chronic familial icterus, but treatment can help to manage the symptoms and prevent complications. Treatment options include:

Phototherapy: This involves exposing the skin to ultraviolet light, which helps to break down bilirubin. Bile acid resins: These medications bind to bile acids in the intestine, preventing their reabsorption and increasing the excretion of bilirubin. Liver transplant: In severe cases, a liver transplant may be necessary to replace the damaged liver.

Prognosis

The prognosis for chronic familial icterus depends on the severity of the enzyme deficiency. In most cases, the condition is mild and does not lead to significant health problems. However, in severe cases, liver damage and cirrhosis can occur, which can shorten life expectancy.

Complications

Chronic familial icterus can lead to several complications, including:

• Liver damage and cirrhosis
• Gallstones
• Jaundice-associated encephalopathy (a condition characterized by confusion and impaired mental function)
• Increased risk of infections

Prevention

There is no known way to prevent chronic familial icterus. However, genetic counseling can help individuals who carry the mutated gene to understand their risk of having children with the condition.

Conclusion

Chronic familial icterus is a rare inherited disorder that causes persistent jaundice from birth. It is caused by a deficiency of the UGT enzyme, which is responsible for converting bilirubin into a water-soluble form that can be excreted in bile. Treatment options include phototherapy, bile acid resins, and liver transplant. The prognosis for chronic familial icterus depends on the severity of the enzyme deficiency.