Monogenic diabetes is an important but under-recognised cause of diabetes mellitus, particularly in settings with limited access to genetic testing. A retrospective case series of seven individuals with genetically confirmed monogenic diabetes managed at tertiary academic centres in Cape Town is described to emphasise that these conditions occur in South Africa. Patients with mutations associated with maturity-onset diabetes of the young, neonatal diabetes, mitochondrial diabetes, and syndromic insulin resistance were identified. Diagnostic reassessment was prompted by early-onset diabetes, preserved endogenous insulin secretion, negative islet autoantibodies, syndromic features, or unexpected treatment responses. Genetic confirmation had important implications for treatment, prognosis, and family screening. This case series demonstrates that monogenic diabetes occurs across a broad phenotypic spectrum in South Africa and that recognition in routine clinical practice leads to meaningful changes in management, surveillance, and family counselling.
Background: Red cell distribution width (RDW) is a prognostic marker in cardiovascular and kidney disease, but its significance in African populations with high burdens of diabetes and HIV is unclear. Methods: 135 adults attending a diabetes clinic in South Africa were retrospectively analysed. Kidney dysfunction was defined as eGFR < 60 ml/min/1.73 m(2) or abnormal proteinuria defined as urine protein:creatinine ratio (uPCR) > 0.015 g/mmol or dipstick >= 1+ when uPCR was missing. Associations between RDW and kidney dysfunction were assessed using correlation tests and multivariable logistic regression in this cross-sectional analysis. Results: Kidney dysfunction was present in 90/135 patients (66.7%): 29 by eGFR < 60 alone, 28 by abnormal proteinuria alone, and 33 by both. RDW did not differ significantly between those with and without kidney dysfunction (13.6 +/- 1.7% vs. 13.2 +/- 1.6%, p = 0.19). RDW was not correlated with eGFR (rho = -0.10, p = 0.26) or uPCR (rho = -0.04, p = 0.68) and showed only a weak trend with HbA1c (rho = -0.15, p = 0.08). In multivariable regression, age (OR 1.10 per year, 95% CI 1.04-1.17, p = 0.001), and HIV-positive status (OR 4.36, 95% CI 1.06-17.98, p = 0.042) were independently associated with kidney dysfunction. RDW was not predictive (OR 1.23, 95% CI 0.90-1.67, p = 0.19). Conclusion: RDW was not independently associated with kidney dysfunction in this cohort. Age and HIV infection remained independently associated with kidney dysfunction. Proteinuria was incorporated into the composite outcome definition and therefore was not treated as an independent predictor.
