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@#The majority of patients with congenital adrenal hyperplasia (CAH) present with a deficiency of 21-hydroxylase or 11-beta-hydroxylase, which account for 90% and 7% of cases, respectively. However, CAH due to 17α-hydroxylase deficiency (17OHD) is an extremely rare form of CAH (<1% of all CAH cases) that leads to a deficiency of cortisol and sex steroids, along with features of aldosterone excess. This is a case of a 51-year-old single female who was referred to us for the evaluation of new-onset hypertension and hypokalaemia of one-year duration. She was born out of a second-degree consanguineous marriage and reared as a female. She was diagnosed to have testicular feminization syndrome when she presented with a history of primary amenorrhea, absence of secondary sexual characteristics, and bilateral labial swellings at pubertal age. Subsequently, she underwent gonadectomy at the age of 16. Due to the presence of hypertension, metabolic alkalosis and bilaterally enlarged adrenals on CT scan, 46, XY disorders of sexual development (DSD) was considered. A karyotype confirmed the presence of 46, XY chromosomal sex, and genetic analysis revealed a mutation in the CYP17A1 gene, thus confirming the diagnosis of 17a-hydroxylase deficiency.

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We report the optical characteristics of relatively large sized (∼7.0-8.0 µm) but low aspect ratio Ge microdisks grown on a virtual Si0.5Ge0.5 substrate using molecular beam epitaxy following the Stranski-Krastanov growth mechanism. Grown microdisks with very low aspect ratio Ge islands exhibit direct band gap (∼0.8 eV) photoluminescence emission sustainable up to room temperature, enabled by the confinement of carriers into the microdisks. p-i-n diodes with an intrinsic layer containing Ge microdisks have been fabricated to study their emission and photoresponse characteristics at an optical communication wavelength of ∼1550 nm. A strong electroluminescence at 1550 nm has been achieved at low temperatures in the device for a very low threshold current density of 2.56 µA cm-2 due to the strong confinement of injected holes. The emission characteristics of the fabricated device with respect to the injected current density and temperature have been studied. Novel emission and optical modulation characteristics at 1550 nm of the fabricated p-i-n device containing Ge microdisks grown on a virtual SiGe substrate indicate its potential for Si CMOS compatible on-chip optical communications.