Progressive short stature in Pearson syndrome and the impact of organ failure

BACKGROUND: Pearson syndrome (PS) is a rare, unique primary mitochondrial disorder characterized by single large-scale mitochondrial DNA deletions, bone marrow failure, lactic acidosis, and progressive multi-organ complications. METHODS: We retrospectively evaluated anthropometric data from 25 patients with PS. RESULTS: The median height, weight, and body mass index (BMI) standard deviation scores (SDS) at the last measurement were - 1.95 (range: -7.32 to 1.09), -1.70 (range: -12.26 to 0.11), and - 1.52 (range: -5.01 to 2.19), respectively; 50%, 40%, and 37.5% of patients, respectively, had values below -2 SDS. Longitudinal data from 18 patients showed that height and weight SDS declined progressively with age in most patients, whereas BMI SDS fluctuated without a clear age-related trend. Initiation of tube feeding improved weight and BMI SDS in some patients, while height SDS continued to decline without catch-up growth. Patients with organ failure exhibited an earlier decline in height SDS than those without organ failure. CONCLUSIONS: Patients with PS are generally short and underweight, and their short stature worsens over time. The presence of organ failure further exacerbates growth impairment.