The African Journal of Laboratory Medicine focuses on the role of the laboratory and its professionals in the clinical and public healthcare sectors, and is specifically based on an African frame of reference.

Background: Hypoparathyroidism, sensorineural deafness and renal disease (HDR) syndrome, also known as Barakat syndrome, is a rare autosomal dominant genetic disorder manifesting as a result of haploinsufficiency of the GATA3 gene. GATA3 is a member of zinc-finger transcription factors that are responsible for the embryonic development of key organs and structures including the parathyroid glands, auditory system and kidneys. Here, we report the first African case of HDR syndrome to be confirmed by chromosomal microarray analysis (CMA). Case presentation: A 3-month-old female presented with focal seizures due to severe hypocalcaemia associated with low parathyroid hormone. The patient also had sensorineural hearing loss, global developmental delay and prominent dysmorphic features that included a tall, prominent forehead, long, curly eyelashes, a depressed nasal bridge as well as subtle skeletal abnormalities. The dysmorphic features, global developmental delay and hypoparathyroidism associated with persistent and severe hypocalcaemia led to the investigation by CMA which detected a 9.5 Mb heterozygous terminal loss of chromosome 10p15.3p14; GATA3 is included in this region. In addition, CMA detected a 4.4 Mb heterozygous interstitial gain of chromosome 10p14p13 indicating the presence of an inverted duplication and deletion of chromosome 10p. The patient was actively treated with IVI calcium gluconate, oral calcium carbonate and alfa cholecalciferol. Conclusion: This case emphasizes that complex patients with developmental delay and multiple congenital anomalies are likely to benefit from evaluation by CMA. Indeed, this approach still has an important role to play, particularly in inadequately resourced settings such as in Africa, for the investigation of patients with complex genetic disorders associated with significant chromosome aberrations.

Introduction: Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder that leads to impaired cortisol and/or aldosterone biosynthesis with simultaneous shunting to the intact androgen pathway. In contrast to females, males with CAH due to 21-hydroxylase deficiency may not always be detected at birth, and are often diagnosed later in life subsequent to life threatening adrenal crises and excessive virilization. Case Report: Our case is a 9-year-old boy who presented at the age of 4 years with tall stature, a large penis, pubic hair as well as mild intellectual disability. His biochemical results revealed low follicle-stimulating hormone (FSH) and luteinizing hormone (LH) (1.0 IU/L for both), elevated testosterone 12.5 nmol/L (0.1–0.9), and elevated 17-OH progesterone 87.0 nmol/L (0.5–2.2). Radiological imaging showed physeal closure in consonance with the age of 17 years, normal appearance of the adrenal glands on magnetic resonance imaging (MRI), however, adrenal rests were detected in his testes. The diagnosis was confirmed by biallelic pathogenic variants namely, c.293-13C>G splice site variant and c.955G>A p.(Gln319Ter) in the CYP21A2 gene. Conclusion: The unavailability of universal newborn screening (NBS) in the low-and-middle-income countries contributes to treatable conditions such as CAH being missed particularly in male patients leading to potentially dire consequences to affected patients and their families. Comprehensive clinical assessment, together with appropriate laboratory and radiological investigations are fundamental for timely diagnosis and treatment of non-classical CAH.

Background: Numerous CVD risk assessment models exist to estimate the 10-year risk of CVD for individuals; among these, the Framingham risk model is notable

Newborn screening is a cornerstone of preventive neonatal healthcare, enabling the early detection and treatment of serious congenital disorders before the onset of irreversible complications. Advances in next-generation sequencing technologies have led to growing interest in genomic newborn screening (gNBS) as a strategy to expand the scope and diagnostic capabilities of conventional screening programs. This chapter reviews the principles, clinical applications, challenges, and future directions of gNBS. The sequencing approaches, including targeted exome sequencing, whole-exome sequencing, and whole-genome sequencing, are discussed, highlighting their respective advantages, limitations, and diagnostic utility. Emphasis is placed on the interpretation and reporting of genomic findings, including variant classification, the role of parental testing, management of variants of uncertain significance, and the use of complementary technologies such as functional studies. The chapter explores the ethical, legal, and psychosocial implications of gNBS, including informed consent, privacy, data sharing, secondary findings, psychological impact, and the rights of children and families. Emerging innovations such as artificial intelligence, multi-omics integration, pharmacogenomics, and gene therapy are examined for their potential to enhance diagnostic accuracy and support precision medicine from early life. While gNBS offers opportunities for the timely diagnosis and management of genetic disorders, significant technical, logistical, economic, and governance challenges remain. Successful implementation will require robust laboratory infrastructure, skilled multidisciplinary teams, clear regulatory frameworks, and equitable access to genomic services. As evidence accumulates, gNBS is poised to play an increasingly important role in neonatal healthcare, with the potential to transform disease prevention, diagnosis, and personalized management for future generations worldwide.