Colchicine is a lipophilic drug used to treat various conditions, including gout, primary biliary cirrhosis, familial Mediterranean fever, and several other disorders. It possesses a very narrow therapeutic index that predisposes to poisoning. Patients initially present with gastrointestinal complaints followed by multiorgan failure (the liver, heart, and kidneys are mainly affected) and bone marrow suppression that leads to sepsis. The diagnostic workup must confirm the recent use of this drug, whereas a full laboratory workup is necessary to determine the extent of organ damage.
The clinical presentation of colchicine poisoning stems from the potent effects of the drug   . Colchicine disrupts the assembly of microtubules and higher doses can promote severe disruption of various cellular mechanisms   . The majority of studies describe colchicine poisoning in three phases   :
Although the presentation of colchicine poisoning consists of nonspecific gastrointestinal and systemic symptoms, the physician must obtain a detailed patient history and conduct a thorough laboratory workup in order to narrow down the differential diagnosis. Colchicine is extensively metabolized in the liver (and in the kidneys to some extent), meaning that several drugs may enhance its effect, eg. statins, antimicrobial drugs (clarithromycin, erythromycin, and ketoconazole), cyclosporine, but also grapefruit juice  . For this reason, medication history is particularly important for identifying possible poisoning due to colchicine . After assessing the course and progression of symptoms, a comprehensive laboratory assessment is mandatory. Typical findings in colchicine poisoning are high creatine phosphokinase levels (CPK, or CK), lactic acidosis, azotemia (pre-renal), electrolyte imbalance, and abnormally high liver transaminases, whereas coagulopathies are also found in some cases   . Leukocytosis is seen in the initial stages, but severe leukopenia and pancytopenia are detected in the multi-organ damage phase, due to bone marrow suppression . Electrophysiologic studies may be of use in the setting of an undisclosed diagnosis, showing specific patterns of motor unity myopathy in muscles of the trunk and the proximal limbs and complex repetitive discharges  .