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Most cases of hypertension are because of essential hypertension, however 5% - 15% of cases can be a result of a secondary cause. In this article, we focus on the endocrine causes of secondary hypertension with a particular focus on pheochromocytomas (PCCs) and paragangliomas (PGLs). Around 15 endocrine disorders can initially present with hypertension. Amongst those PCCs and PGLs are rare but potentially life-threatening causes. An early diagnosis and timely referral can be life-saving. Herein, we present an approach for screening and diagnosis of these patients and focus on the importance of genetic testing.

A germline mutation is identified in almost 40% of pheochromocytoma/paraganglioma (PPGL) syndromes. Genetic testing and counseling are essential for the management of index cases as well as presymptomatic identification and preemptive management of affected family members. Mutations in the genes encoding the mitochondrial enzyme succinate dehydrogenase (SDH) are well described in patients with hereditary PPGL. Among patients of African ancestry, the prevalence, phenotype, germline mutation spectrum, and penetrance of SDH mutations is poorly characterized. We describe a multifocal paraganglioma in a young African male with an underlying missense succinate dehydrogenase subunit B (SDHB) mutation and a history of 3 first-degree relatives who died at young ages from suspected cardiovascular causes. The same SDHB mutation, Class V variant c.724C>A p.(Arg242Ser), was detected in one of his asymptomatic siblings. As there are limited data describing hereditary PPGL syndromes in Africa, this report of an SDHB-associated PPGL is a notable contribution to the literature in this growing field. Due to the noteworthy clinical implications of PPGL mutations, this work highlights the existing need for broader genetic screening among African patients with PPGL despite the limited healthcare resources available in this region.

Paraneoplastic or ectopic Cushing’s syndrome (CS) is a rare cause of endogenous hypercortisolism. It is due to ectopic adrenocorticotropic hormone (ACTH) secretion and has been reported in association with a variety of neuroendocrine tumors such as small-cell lung carcinoma, carcinoid tumors, and medullary carcinoma of the thyroid. Paragangliomas (PGLs) are rare neuroendocrine tumors that can secrete catecholamines. Case reports and reports of ectopic ACTH secretion from metastatic PGLs causing CS are exceedingly rare. We present a case of a 38-year-old female, who presented with typical signs, symptoms, and complications of CS, secondary to a PGL with widespread metastases, which eventually led to her demise.

Hyperprolactinaemia is a common endocrine abnormality in patients with kidney failure. A 43-year-old female, known with kidney failure on maintenance haemodialysis, was referred with symptomatic hyperprolactinaemia. Biochemical investigations revealed a markedly elevated serum prolactin level. Magnetic resonance imaging of the brain (without gadolinium) demonstrated a pituitary macroadenoma. The patient was started on cabergoline therapy. This case discusses hyperprolactinaemia in kidney failure and highlights the importance of investigating markedly elevated prolactin levels. In cases where patients have galactorrhoea, headaches and/or visual disturbances, clinicians should be alert to the possibility of a prolactin-secreting pituitary tumour.

Pheochromocytomas and paragangliomas (PPGL) are rare neuroendocrine tumors arising from adrenal and extra-adrenal paraganglia. Up to forty percent are due to an underlying germline mutation. Mutations in the subunit B gene of the SDH complex (SDHB) are associated with PGL syndrome four. A 34-yr-old African man from Southern Africa presented with a two-year history of sustained hypertension associated with the classic triad of sweating, headaches and palpitations. Family history was contributory towards early unexpected deaths of his father (age 42) and two younger brothers (ages 13 and 14 respectively). On examination his blood pressure was persistently elevated measuring 146/87mmHg. In view of the classic presenting symptoms and hypertension onset at a young age, a PPGL was suspected. Biochemical investigations were positive with an elevated 24-hour urine normetanephrine level of 35807 (480-2424nmol/24hours), normal metanephrine level of 689 (264-1729nmol/24hours), an elevated normetanephrine:creatinine ratio of 3270 (28-158nmol/mmol creatinine) and an elevated methoxytyramine level 4941.69nmol/24 hours (A p.(Arg242Ser) and hence PGL4 syndrome. The patient underwent staged surgery with successful removal of the intra-abdominal tumor. Unfortunately, due to peri-operative complications associated with the second surgery, the patient demised. Histopathological examination of both tumors was consistent with a paraganglioma. Genetic counselling and testing were offered to all living first-degree relatives. His sister tested positive for the same pathological variant. His 6-week-old son will be offered counselling and testing at a later stage. To the best of our knowledge, we are the first to describe the missense SDHB mutation (pathogenic variant c.724C>A p.[Arg242Ser]) and the occurrence of an SDHB associated PGL in a family of African ethnicity. This case highlights the importance of genetic counselling and testing in patients with a confirmed PPGL. Due to resource limitation the African population remains under represented in genetic studies which limits the utility of precision medicine in this group. As such, our case is an important addition to the body of knowledge in this growing field and highlights the need for cost effective genetic screening tools in low resourced settings.

Background: The incidence of type 2 diabetes mellitus (T2DM) is increasing rapidly. This is possibly due to increasing obesity, reduced level of activity, sedentary lifestyle, ageing population and industrialisation.Aim: The primary objective of this study was to ascertain the level of activity using a pedometer. The secondary objectives were: (1) to correlate the baseline level of activity with body mass index (BMI), HbA1c and blood pressure (BP), (2) to assess whether 7 000 steps a day influence HbA1c and BP over a three-month period.Method: A total of 110 patients were screened; 95 patients (n = 95) completed the study. At the first visit HbA1c, BMI and BP were measured. At the end of the first month baseline physical activity was recorded using pedometers. Patients were divided into two groups: active (n = 50) and control (n = 45). Patients in the active group were asked to walk a minimum of 7 000 steps/day. The control group were asked to continue their usual activity. These patients were followed up monthly over a period of three months. At each visit BMI, BP and step counts were recorded. HbA1c was measured only at the first and last visit.Result: Activity levels increased significantly in the active group throughout the study. Mean step count for the control group at baseline was 2 923.1 ± 1 136.9, which increased to 3 431.2 ± 1 251.7 by the end of the study. Mean step count for the active group at baseline was 4 609.9 ± 1 702.1, which increased to 7 244.8 ± 1 419.4 by the end of the study. The difference between control and active group was statistically significant (p < 0.001). Systolic and diastolic BP decreased significantly in both groups (p = 0.017) for systolic BP and (p = 0.002) for diastolic BP but no interaction was found between the groups as systolic and diastolic BP decreased at the same rate over time in both groups. HbA1c decreased by 1.04% in the active group; this difference was statistically highly significant (p < 0.001).Conclusion: Increase in activity levels decreases HbA1c by 1.04 percentage point over three months in T2DM (p < 0.001), which is statistically significant.Keywords: BMI, HbA1c, pedometers, physical activity, T2DM