Conn´s syndrome after kidney transplantation.

Conn's syndrome, defined as unilateral aldosterone-producing adenoma, accounts for 35-40% of cases of primary hyperaldosteronism. Primary hyperaldosteronism typically occurs in younger patients with poorly controlled arterial hypertension due to extracellular fluid retention, in whom at least a triple combination of antihypertensives, including a diuretic, is needed to maintain normotension. The clinical picture of arterial hypertension may be complemented by symptoms associated with hypokalaemia, such as weakness, fatigue, palpitations, convulsions, polydipsia, or polyuria. In addition to arterial hypertension and hypokalaemia, the diagnosis of Conn's syndrome relies on examination of serum renin and aldosterone concentrations, plasma renin activity, exercise or furosemide stimulation tests, and imaging studies, preferably computed tomography. The method of treatment of Conn's syndrome is adrenalectomy. In patients with primary hyperaldosteronism with underlying bilateral adrenal cortical hyperplasia or patients contraindicated for surgery, mineralocorticoid receptor antagonists are administered in combination with antihypertensives targeted for optimal blood pressure control.In the group of patients after kidney transplantation, the exact incidence of primary hyperaldosteronism is unknown. Based on a cross-sectional study performed in 2020, it is estimated to be approximately 15% in the group of patients with unsatisfactorily compensated arterial hypertension; in the cohort of normotensive recipients, the incidence of primary hyperaldosteronism is not documented. Diagnosis of Conn's syndrome in patients in the early period after kidney transplantation is problematic, as the prevalence of arterial hypertension in transplanted patients is high (70-90%) according to the literature. Mineral abnormalities, including hypokalaemia, are also common in the early post-transplant period, mainly due to factors such as duration of cold ischaemia, onset of graft function, donor parameters, post-transplant tubulopathy, and diuretics, the effects of immunosuppressive drugs (especially calcineurin inhibitors and corticosteroids), and possibly potassium-restricted dietary habits that the patient brings from the pre-transplant period, which may mask the effect of hyperaldosteronism on potassium.We present the case of a patient who was diagnosed with Conn's syndrome 7 months after primary kidney transplantation from a deceased donor based on persistent hypokalaemia unresponsive to replacement therapy. At the time of the first manifestation of severe hypokalaemia, the patient was treated with a dual combination of antihypertensives (amlodipine at a daily dose of 5 mg and carvedilol at a daily dose of 50 mg), without the need for a diuretics.We consider the case interesting because the spectrum of mineral and acid-base abnormalities in advanced renal failure and in the early post-transplant period, as well as acid-base and mineral imbalances, including hypokalaemia, and the high prevalence of arterial hypertension in the post-transplant period, may mask the picture of Conn's syndrome (Fig. 3, Ref. 19). Text in PDF www.elis.sk Keywords: kidney transplantation, primary hyperaldosteronism, hypokalaemia, metabolic alkalosis, secondary arterial hypertension.

Early recurrence of focal segmental glomerulosclerosis as an unusual cause of primary kidney transplant malfunction.

Recurrence of the primary disease is one of the most common causes of graft failure in the first decade after kidney transplantation. We present a case of a patient with an unusually rapid recurrence of focal segmental glomerulonephritis in the graft, the recognition of its occurrence was hampered by the primary graft affection and oligoanuria and by insignificant histological changes in the first two biopsy samples in the early post-transplant period, as well as by unawareness of the disease leading to terminal renal failure, as no renal biopsy was performed due to grade 3 obesity. Only worsening of hypoalbuminemia and finding of massive proteinuria despite oligoanuria were crucial for further management. Disease recurrence in the graft was confirmed by electron microscopy. However, complex targeted therapy did not result in restoration of graft function and decrease in proteinuria. This case history was aimed to draw attention to the knowledge of the importance of the primary disease confirmed by renal biopsy and early (so called pre-emptive) treatment in case of diseases with a high potential of recurrence (Fig. 7, Ref. 10). Text in PDF www.elis.sk Keywords: kidney transplantation, recurrence, minimal changes in glomeruli, focal segmental glomerulosclerosis.