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Retrospective analysis of children with α-1 antitrypsin deficiency
Atakan Comba1, Fatma Demirbaş, Gönül Çaltepe
1Department of Pediatric Gastroenterology, Hepatology and Nutrition, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey.
Insights
Alpha-1 Antitrypsin (AAT) deficiency in children often leads to chronic liver disease. Even with normal enzyme levels, heterozygous AAT deficiency can cause delayed diagnosis in pediatric patients.
Area of Science:
- Pediatric Hepatology
- Genetic Liver Disorders
- Biochemistry
Background:
- Alpha-1 Antitrypsin (AAT) deficiency is a common genetic liver disorder, typically associated with chronic liver disease and cirrhosis in adults.
- While common in adults, chronic liver disease and cirrhosis due to AAT deficiency are rare in children, making pediatric cases particularly noteworthy.
Purpose of the Study:
- To investigate the clinical features of children diagnosed with AAT deficiency.
- To compare the presentation and outcomes of homozygous (PiZZ) versus heterozygous (PiMZ) AAT deficiency in pediatric patients.
Main Methods:
- A cohort of 20 children with mutant Pi alleles underwent AAT phenotyping and clinical assessment.
- Data collected included presenting symptoms, physical examination, laboratory results, liver biopsy findings, and follow-up data.
- Exclusion criteria focused on ruling out infectious, anatomic, and metabolic causes of liver disease.
Main Results:
- The study included 20 children (6 female, 14 male) with a mean age of 6.3 years. Eight patients (40%) had PiZZ phenotype, and 12 (60%) had PiMZ phenotype.
- Elevated liver function tests were the most common symptom. Three patients presented with neonatal cholestasis, and one with compensated cirrhosis.
- Liver biopsies revealed characteristic globules in hepatocytes in all but one patient. At follow-up, all PiZZ patients had chronic hepatitis (one with cirrhosis), and two PiMZ patients had chronic hepatitis.
Conclusions:
- Classical AAT deficiency frequently manifests as chronic liver disease in children.
- Heterozygous (PiMZ) AAT deficiency can present with fluctuating enzyme levels, potentially leading to delayed diagnosis in pediatric populations.
Background:
α-1 Antitrypsin (AAT) deficiency is the most frequently occurring genetic liver disorder. The association among classical α-1 antitrypsin deficiency (AATD), chronic liver disease, and cirrhosis is common in adult patients but rare in children.
Aim:
To assess the clinical characteristics of children with AATD and to compare symptoms between homozygous and heterozygous children.
Materials And Methods:
The study included 20 children who were found to have mutant Pi alleles. AAT phenotyping was conducted on patients with a low serum AAT level. The exclusion criteria included infectious, anatomic, and metabolic conditions. Symptoms on presentation, physical examination findings, laboratory values, liver biopsy results, and follow-up periods were recorded for each patient.
Results:
The patients included six (30%) girls and 14 (70%) boys, with a mean age of 6.3±5.1 (1-16) years. The PiZZ phenotype was present in eight (40%) and PiMZ in 12 (60%) patients. The most frequent symptom was elevated liver function test results. Three patients were referred with neonatal cholestasis and one with compensated cirrhosis. Eight patients underwent liver biopsy; all patients except one had periodic acid-Schiff-positive diastase-resistant globules in the hepatocytes. The mean follow-up period was 34±33 (12-101) months. At the end of follow-up, all patients with PiZZ were found to have chronic hepatitis, and one with cirrhosis. On the contrary, two patients with PiMZ were found to have chronic hepatitis.
Conclusion:
Children with classical AATD commonly have chronic liver disease. In heterozygous (PiMZ) children with AATD, enzyme levels can normalize with occasional fluctuations, sometimes causing delayed diagnosis.
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