The diagnostic odyssey, clinical burden, and natural history of Barth syndrome: an analysis of patient registry data

Abstract

Aim: Barth syndrome (BTHS; OMIM 302060) is an ultra-rare, complex, multi-system X-linked disorder that arises from pathogenic mutations in the gene TAFAZZIN. BTHS is characterized by cardiomyopathy, skeletal myopathy, muscle weakness, and neutropenia. To better understand the natural history and lived experience of affected individuals, the Barth Syndrome Foundation maintains the patient-inputted Barth Syndrome Registry and Repository (BRR).

Methods: Available cross-sectional and longitudinal participant data (n = 115) were analyzed to illustrate the diagnostic odyssey, manifestations, and healthcare utilization across a broad range of affected individual age groups.

Results: Individuals who experienced cardiomyopathy or heart failure as the first manifestation had the shortest times to diagnosis compared to less appreciated manifestations (e.g., frequent infections, poor muscle tone, growth delay). The most frequently reported manifestations across all ages were due to cardiac disorders (80.7%), gastrointestinal (GI) disorders (68.7%), neutropenia or frequent infections (67.2%), and fatigue (60.9%), with 47.1% of participants scoring in the moderate-to-severe range of the Patient-Reported Outcomes Measurement Information System (PROMIS) Fatigue Short Form 8A survey. Participants saw, on average, 3.6 specialists in the previous year, with cardiologists (97.9%) and hematologists (58.2%) being the most commonly seen specialists.

Conclusion: The data suggest that cardiac disorders are the most common manifestations of BTHS, but also reveal a high frequency of feeding and GI-related issues that previous reports have not captured. Physician-targeted education on the lesser-known symptoms and population-based screening for BTHS may aid in timely diagnosis and improved clinical management.

Keywords

Barth syndrome / natural history / diagnostic odyssey / cardiomyopathy / neutropenia / gastrointestinal / fatigue

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