Objective: To analyze the clinicopathological features of pseudohypoparathyroidism (PHP), that would help clinicians to consider this rare condition in children.
Methods: A retrospective review of nine patients with PHP (including seven males and three females) admitted to our hospital between 1990 and 2014 was conducted. Clinical and biochemical parameters along with epidemiological data were extracted and analyzed.
Results: The mean age at diagnosis was 61.8±26.1 months, ranging from 4 to 114 months. The most frequent clinical features were: round lunar face and obesity (77.7%), followed by brachydactyly and learning/behavior disabilities (66.7%). Subcutaneous calcifications, although a landmark of PHP, were only present in four patients (44.4%). Afebrile seizures occurred in two cases, despite the majority showed multiple intracranial calcifications on cranial CT scan. Laboratory tests at diagnosis revealed most frequently hypocalcemia (mean 7.4±1.9 mg/dl; 8.610.2), hyperphosphatemia (mean 7.9±1.7 mg/dl; 2.74.5) and high PTH levels (mean 366.3±218.4 pg/ml; 1472). Subclinical hypothyroidism was present in eight out of nine patients (88.8%) with a mean TSH of 9.45±4.2 uU/ml (0.355.5) and a mean free T4 of 0.95±0.1 ng/dl (0.81.9). Vitamin D3, and calcium when needed, were prescribed to all patients to prevent symptomatic hypocalcemia and presumably to stop disease progression by lowering the PTH levels, although it is not clear whether this normalization is beneficial. Genetic testing was performed in six children.
Conclusion: PHP is a rare and heterogeneous genetic disease with a high rate of misdiagnosis and no specific treatment. It should be considered in children presenting with a round face, obesity, brachydactyly, learning/behavior disabilities, subcutaneous calcifications and subclinical hypothyroidism. Laboratory evaluation of blood calcium, phosphorus, PTH and thyroid hormones should be ordered as soon as possible, as well as neuroimaging and a genetic profile for further confirmation.
20 - 23 May 2017
European Society of Endocrinology