Understanding Cystinosis, Clinical Characteristics and Hypothyroidism Prevalence in Iraqi Pediatric Patients

Background: Cystinosis, an autosomal recessive lysosomal storage disease, leads to the abnormal accumulation of cystine, primarily affecting the kidneys. Despite various treatments, including cysteamine therapy, renal replacement, and hormonal interventions, no curative treatment exists. Hypothyroidism is a common complication in cystinosis patients, but its prevalence and associations require further investigation. This study aimed to assess the prevalence of hypothyroidism in cystinosis patients and identify associated risk factors. Methods: A six-month cross-sectional study was conducted at Al-Ramadi Teaching Hospital, Iraq, involving 92 cystinosis patients. Data were collected from patient records, and thyroid dysfunction was defined by abnormal thyroid hormone levels. Results: Hypothyroidism prevalence among cystinosis patients was 40.2%. It significantly increased with patient age and age at cystinosis diagnosis, reaching 85.7% and 87.5% in patients over 10 years and diagnosed after 2 years of age, respectively. A positive family history of cystinosis correlated with higher hypothyroidism prevalence. Conclusion: Hypothyroidism is prevalent (40.2%) in cystinosis patients, particularly in older individuals with delayed diagnosis or cysteamine initiation, and those with a family history of the disease. Timely diagnosis, early cysteamine therapy initiation, and regular monitoring for hypothyroidism are essential for managing cystinosis-associated endocrine complications. Further research should explore additional factors influencing hypothyroidism in cystinosis patients to optimize treatment and outcomes.