Phenotype variation among siblings with 5-alpha reductase deficiency: A case series

5-Alpha reductase deficiency; an important cause of 46, XY DSD: Report of three cases within a family

Key clinical message

5-Alpha reductase deficiency is an important cause of 46, XY disorder of sex development. Timely diagnosis and proper management by a multidisciplinary team can lead to a favorable outcome. Sex assignment should be deferred until puberty because spontaneous virilization occurs and the patient can engage in the decision-making process.

Abstract

5-Alpha reductase deficiency is a genetic disorder causing 46, XY disorder of sex development (DSD). Typical clinical feature is a male with ambiguous genitalia or undervirilization at birth. Here we report three cases of this disorder within a family.

Disorders of sex development (DSD) 46.XY due to type 2 5-α reductase deficiency in three siblings: Case report from a low-resource setting

Introduction and Importance

Disorders of Sexual Development (DSD) is a rare autosomal recessive genetic condition significantly affecting patients' lives in various aspects, particularly psychosocially. Type 2 5-α reductase is a cause of DSD 46,XY. It is rare to find multiple DSDs in the same family. Patients may present with amenorrhea and ambiguous genitalia. This case report is aimed to highlight the genetic aspects of the disease, the challenges to diagnostics and the various management options for the patients.

Methods

Case series of three siblings with DSD 46, XY with relevant discussion.

Outcomes

Three sisters, aged nineteen, seventeen, and fifteen years old came with an identical complaint of late menarche. Their physical examinations revealed elementary breast development and little axillary hair. The external genitals consisted of vulva, major and minor labia. Clitoromegaly was present with short (<5 cm) vagina. No female internal genital was found but undescended testes were palpable. Presences of testes was confirmed via ultrasound. Laboratory results showed reduced estradiol, highly increased follicle stimulating hormone (FSH), normal male testosterone levels and increased testosterone-dihydrotestosterone ratio (T/DHT >20). Karyotype was 46,XY. Diagnoses of DSD 46, XY due to type 2 5-α reductase deficiency were established. Patient 1 chose female as the gender of choice whilst patients 2 and 3 chose male. All patients are due for corrective surgery along with psychotherapy and psychoeducation.

Conclusion

DSD 46, XY due to type 2 5-α reductase deficiency is a rare autosomal recessive genetic disorder requiring comprehensive diagnostics and holistic management to improve patient quality of life.

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Disorder of sexual development (46,XY) due to type 2 5-α reductase deficiency is rare.

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It requires a multidisciplinary team involving a battery of tests, imaging and genetic tests, e.g. karyotyping.

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Informed consent and collaboration with other disciplines are pivotal for holistic management.