RESUMO
Development of the extreme form of hypothyroidism defined as myxedema is very rare. Acute symptoms and their management have been described in detail previously. However, not much attention has been devoted to therapeutic challenges that are faced in the recovery phase of the treatment, especially pertaining to the gastrointestinal system. The link between myxedema and the appearance of severe Clostridium difficile infection (CDI) has not been established so far. A 61-year-old woman with no significant medical record was admitted to hospital because of infected heel pressure and thyroid dysfunction. A week later, due to hypothermia, hypotension, and unconsciousness, she was transferred to the intensive care unit. The clinical picture and the results of laboratory tests confirmed diagnosis of myxedema. After the introduction of resuscitative measures and hormonal substitution, patient's condition stabilized within 10 days. Due to concomitant sepsis, initially piperacillin/tazobactam and later cefuroxime were administered. After 20 days of antibiotic therapy, the patient developed CDI that was resistant to the routine mode of treatment. The clinical recovery was achieved only after a fecal microbiota transplantation procedure. The function of the digestive tract in myxedema is disturbed by gastric achlorydia and reduced peristalsis, which in turn can predispose the small intestine to overgrowth of bacteria. The use of antibiotics can additionally decrease the intestinal bacterial diversity, favoring the overgrowth of Clostridium difficile. The authors conclude that myxedema may increase the likelihood of a treatment-resistant form of CDI that requires the implementation of fecal microbiota transplantation.