Cholesterol microembolization syndrome: a complication of anticoagulant therapy

Renal cholesterol crystal embolism in the setting of warfarin use

A 73-year-old man presented for evaluation of weakness and black tarry stools that occurred 1 day prior to admission. His medical history is significant for diabetes mellitus, stage 3 chronic kidney disease and deep vein thrombosis on warfarin. He was admitted to the hospital and was found to have acute kidney injury and gastrointestinal bleeding due to a supratherapeutic International Normalized Ratio. His hospital course was complicated by persistent decline in his renal function. He was given intravenous fluid resuscitation, fresh frozen plasma and packed red blood cells for his acute blood loss anaemia. Urinalysis was consistent with acute tubular necrosis. Given the persistent rise in creatinine, a kidney biopsy was obtained, and was significant for mild inflammatory changes, without evidence of vasculitis or allergic interstitial nephritis. Histopathological examination with tissue fixation revealed cholesterol embolisation. Given that he had no recent endovascular procedure or instrumentation, this atheroembolic event was attributed to his warfarin use.

Adverse Drug Reactions and Cutaneous Manifestations Associated With Anticoagulation

Anticoagulants are amongst the most commonly prescribed medications worldwide. Although rare, localised and systemic drug reactions have been reported with anticoagulants that can lead to significant morbidity and mortality. Some of the first signs of drug reactions to anticoagulants are cutaneous changes that, when recognised early, can prevent significant complications. Dermatologists should be aware of these changes to make an early and accurate diagnosis. This is particularly important in instances of skin-induced necrosis caused by systemic toxicity to anticoagulants. This review discusses adverse drug reactions to the traditional anticoagulants, warfarin and heparin, and the newer direct oral anticoagulants (DOACs) such as the thrombin inhibitor, dabigatran, and the factor Xa inhibitors, rivaroxaban, apixaban, and edoxaban. In particular, this review provides dermatologists with a framework for early diagnosis and management of patients with drug reactions to anticoagulants and alerts them to potential bleeding complications associated with minor procedures.

Neurodermatology

Since the skin and the central and/or peripheral nervous system share a common source (the ectoderm), numerous genetic and acquired diseases (infectious, tumoral or autoimmune disorders) equally affect both. Neurologic diseases or symptoms such as stroke, cerebral or medullary vascular malformations, peripheral, brain or medullary tumors, epilepsy, ataxia, neurologic infections, or cognitive disorders (dementia, mental retardation) may be associated with specific cutaneous manifestations of which the discovery can facilitate the final diagnosis, thereby leading to specific treatment and/or genetic investigations. Careful examination of the skin, hair, and nails by the neurologist is consequently of the utmost importance; when unusual abnormalities of the skin are discovered or when greater expertise is required, consultation with a dermatologist is frequently advisable.