Pitfalls of diagnosing pituitary hypoplasia in the patients with short stature

Area of Science:

• Pediatric Endocrinology
• Growth Hormone Deficiency
• Diagnostic Imaging

Background:

• Height age (HA) and bone age (BA) delays are common in short stature, potentially leading to overdiagnosis of pituitary hypoplasia when assessed by chronological age (CA).
• Accurate diagnosis of pituitary hypoplasia is essential for appropriate management of growth disorders.

Purpose of the Study:

• To evaluate the diagnostic and prognostic value of pituitary height (PH) and pituitary volume (PV) based on CA, HA, or BA in patients with growth hormone deficiency (GHD).
• To determine the most accurate method for diagnosing pituitary hypoplasia in pediatric patients.

Main Methods:

• Study included 57 patients with severe GHD, 40 with partial GHD, and 39 with idiopathic short stature (ISS).
• Pituitary height (PH) and pituitary volume (PV) were assessed using chronological age (CA), bone age (BA), and height age (HA).
• The correlation between these imaging methods and clinical features was analyzed.

Main Results:

• Pituitary volume (PV) was significantly larger in ISS patients compared to GHD patients.
• PV demonstrated stronger correlations with clinical parameters like height SDS, GH, IGF-1, IGFBP-3, and height velocity.
• Bone age-based PV showed high diagnostic accuracy for differentiating GHD from ISS (Sensitivity: 17%, Specificity: 98%, PPV: 94%).
• Pituitary hypoplasia was identified in 3% of ISS and 17% of GHD patients based on PV-BA.

Conclusions:

• Pituitary volume (PV) assessed by bone age (BA) offers the most accurate diagnostic value for pituitary hypoplasia.
• While BA-based PV improves diagnostic accuracy, potential misdiagnosis remains a consideration.
• PV is also a significant predictor of response to recombinant growth hormone (rGH) therapy.