Laron syndrome presenting with severe low bone density for age in a 28-year-old woman: a case report.

Abstract

Introduction: Laron syndrome (LS) is a rare, autosomal recessive disorder of growth hormone insensitivity, characterized by proportional short stature and low concentrations of insulin-like growth factor-1 (IGF-1) despite normal or increased levels of growth hormone.

Case presentation: A 28-year-old woman presented with proportional short stature and a markedly low body weight, with a BMI of 14.5 kg/m². Physical examination revealed a characteristic phenotype, including a prominent forehead, saddle-shaped nose and blue-tinted sclera. Investigations revealed low serum IGF-1 levels with elevated levels of growth hormone. Severe vitamin D deficiency and secondary hyperparathyroidism were observed. Differentials of malnutrition and clinical hypothyroidism were systematically ruled out. Management was focused on closed fracture reduction, vitamin D and calcium supplementation, and physical rehabilitation of the patient.

Clinical discussion: Based on the phenotypic presentation and endocrine profile of the patient, a clinical diagnosis of LS was formulated. Unlike common LS presentations, this patient was markedly underweight, suggesting ethnic and nutritional variations. The comorbid vitamin D deficiency likely acted as a disease modifier, exacerbating the skeletal complications in an already compromised skeletal system.

Conclusion: This case underscores the importance of strong clinical acumen in diagnosing rare growth disorders, especially in resource-limited settings where confirmatory genetic testing is not readily available. It also highlights how secondary bone disturbances can exacerbate the presentation, leading to significant functional impairment.