Renal Hypokalemia: An Endocrine Perspective.

The majority of disorders which cause renal potassium wasting present with abnormalities in adrenal hormone secretion. While these findings frequently lead patients to seek endocrine evaluation, clinicians often struggle to accurately diagnose these conditions, delaying treatment and adversely impacting patient care. At the same time, growing insight into the genetic and molecular basis of these disorders continues to improve their diagnosis and management. In this review we outline a practical integrated approach to the evaluation of renal hypokalemia syndromes that are seen in endocrine practice while highlighting recent advances in understanding of the genetics and pathophysiology behind them.

Acquired Hemophilia A and urothelial carcinoma.

Acquired Hemophilia A (AHA) is a rare entity, resulting from the production of autoantibodies against Factor VIII of the coagulation cascade. These autoantibodies may develop in response to autoimmune conditions, drugs, neoplastic diseases, and pregnancy. Diagnosis involves clinical presentation, mucocutaneous or intramuscular bleeding, and laboratory findings, such as prolonged activated partial thromboplastin time, decreased levels of Factor VIII, and the presence of Factor VIII autoantibodies. The etiology is diverse, with a variety of underlying culprits. Malignancy-associated AHA has been associated with approximately 15% of cases. Urothelial malignancy-mediated AHA is exceedingly rare, with only two previously published reports. The management of AHA includes stabilization and control of bleeding via the use of hemostatic agents, and elimination of the inhibitor with immunosuppressive therapy. Here, we report a case of AHA secondary to urothelial malignancy and review the pathobiology and pathogenesis of Hemophilia A and AHA.

Lamotrigine-associated hemophagocytic lymphohistiocytosis.

Hemophagocytic lymphohistiocytosis (HLH) is a rare and life-threatening disorder of excessive immune activation. It is mostly seen in the paediatric population and is rarely observed in adults. HLH can be inherited or acquired and is commonly triggered by activation of the immune system by an underlying viral infection or in immune system deficiency such as malignancy or underlying rheumatological disease. HLH is a difficult entity to diagnose due to the rarity of this disorder, variable clinical presentation and non-specific clinical and laboratory findings. HLH carries a high mortality if left untreated, and therefore prompt diagnosis and initiation of immunosuppressive, immunomodulatory and cytostatic medications are critical to improve survival in affected patients. Here, we present a case of lamotrigine-associated HLH. To our knowledge, only eight other cases of lamotrigine-associated HLH have been reported in adult patients.