A rare case of dyskeratosis congenita with DKC1 mutation presenting initially as thrombocytopenia: Case report

RATIONALE: Dyskeratosis congenita is a rare genetic disorder classically characterized by the mucocutaneous triad and bone marrow failure. Diagnosis is challenging when hematologic manifestations precede classic features. PATIENT CONCERNS: A 10-year-old male initially presented with isolated thrombocytopenia, which was misdiagnosed as aplastic anemia. DIAGNOSES: Retrospective examination revealed the mucocutaneous triad. Genetic testing confirmed a pathogenic hemizygous DKC1 mutation (c.1058C>T, p.A353V). INTERVENTIONS: The patient received a 3-month course of androgen therapy. Genetic counseling and prenatal testing were conducted for the family. OUTCOMES: Androgen therapy maintained platelets at 30-60 × 109/L without bleeding or adverse events during follow-up. The asymptomatic mother was a heterozygous carrier. Prenatal testing identified the same mutation in a male fetus, leading to pregnancy termination at 24 weeks. LESSONS: Dyskeratosis congenita can present with isolated cytopenia, risking misdiagnosis. Early genetic confirmation is vital for management and enables informed reproductive planning through prenatal diagnosis. Androgen therapy may be an effective supportive treatment.