Alport syndrome is a genetic disorder affecting the basement membranes of the kidney, ear and eye, and represents a leading cause of monogenic kidney disease. Alport syndrome is genetically heterogeneous with three key genes involved (COL4A3-5) and several transmission patterns, including monogenic Xlinked, autosomal recessive/dominant and digenic. We report a consanguineous family where 13 individuals presented variable features of Alport syndrome including kidney failure on two generations and male-to-male transmission, suggesting autosomal dominant inheritance. COL4A3-5 gene panel analysis surprisingly reveals two distinct, confirmed splice-altering variants in COL4A3 (NM_000091.4: c.1150+5G>A and c.4028-3C>T) present in homozygous or compound heterozygous state in individuals with kidney failure. This adds a further mode of transmission for Alport syndrome where, in a consanguineous family, the independent segregation of two variants at the same locus may create a pseudodominant transmission pattern. These findings highlight the importance of a molecular diagnosis in Alport syndrome for genetic risk counselling, given the variable modes of inheritance, but also the pitfalls of assuming identity by descent in consanguineous families.

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Volume status can be difficult to assess in dialysis patients. Peripheral edema, elevated venous pressure, lung crackles, and hypertension are taught as signs of fluid overload, but sensitivity and specificity are poor. Bioimpedance technology has evolved from early single frequency to multifrequency machines which apply spectroscopic analysis (BIS), modeling data to physics‐based mixture theory. Bioimpedance plots can aid the evaluation of hydration status and body composition. The challenge remains how to use this information to manage dialysis populations, particularly as interventions to improve over hydration, sarcopenia, and adiposity are not without side effects. It is therefore of no surprise that validation studies for BIS use in peritoneal dialysis patients are limited, and results from clinical trials are inconsistent and conflicting. Despite these limitations, BIS has clinical utility with potential to accurately evaluate small changes in body tissue components. This article explains the information a BIS plot (“picture”) can provide and how it can contribute to the overall clinical assessment of a patient. However, it remains the role of the clinician to integrate information and devise treatment strategies to optimize competing patient risks, fluid and nutrition status, effects of high glucose PD fluids on membrane function, and quality of life issues.

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Tuberculosis (TB) infection of the genitourinary tract (GU TB) is rare in renal transplant recipients, with only a few published case series. GU TB is difficult to diagnose with or without immunosuppression but must always be suspected in any patient with unexplained sterile pyuria. As GU TB is associated with graft rejection, prompt diagnosis and treatment are vital. Treatment is challenging, as rifampicin, the most effective drug used to treat tuberculosis, is a significant inducer of cytochrome P-450 3A metabolism, with the potential to cause significant reductions in the serum levels of calcineurin inhibitors. For this reason, rifabutin, a weaker cytochrome P-450 3A inducer, with similar efficacy against TB, is sometimes used as an alternative to rifampicin in transplant recipients. We present a renal transplant patient diagnosed with GU TB, treated with a regime containing rifabutin, who subsequently developed profound hyponatremia and leucopenia. Serum and urine biochemistry was consistent with a diagnosis of the syndrome of inappropriate antidiuretic hormone secretion (SIADH). Both SIADH and leucopenia resolved with rifabutin cessation. This is the first report of biochemically proven, idiosyncratic SIADH and leucopenia associated with the use of rifabutin in the treatment of GU TB in a renal transplant recipient.