Case Presentation: We report a 64-year-old woman with hypertension and lymphangioleiomyomatosis who had recently been hospitalized for C. difficile colitis with profound diarrhea and electrolyte abnormalities. She re-presented with rapidly worsening confusion, tachypnea, hypoxia (SpO₂ 78% on room air), sinus tachycardia up to 140 bpm, hypotension, and diffuse anasarca. Chest imaging showed cardiomegaly, pulmonary edema, and large bilateral pleural effusions. She required intubation, vasopressor support, and bilateral thoracenteses. Initial concerns included cardiogenic, septic, and obstructive shock.Extensive evaluation—including brain MRI, EEG, CT head, CSF analysis, serial cultures, and infectious panels—revealed no infectious or structural cause for her encephalopathy. Echocardiography showed a hyperdynamic EF >70%, inconsistent with cardiogenic shock. Despite antibiotics and aggressive resuscitation, her shock state persisted without clear etiology.Given her recent colitis, significant GI losses, malnutrition risk, macrocytosis, and history of alcohol use, thiamine deficiency emerged as the leading diagnosis. High-dose IV thiamine (500 mg every 8 hours) was initiated. Within 48 hours, she demonstrated dramatic clinical improvement: vasopressors were discontinued, mental status normalized, lactic acidosis resolved, and respiratory failure improved, allowing extubation. Her rapid, robust response confirmed thiamine-responsive mixed Beri-Beri, combining high-output heart failure with metabolic encephalopathy.
Discussion: Thiamine deficiency is an underrecognized cause of high-output heart failure, metabolic encephalopathy, and vasodilatory shock, with presentations that can mimic sepsis or cardiogenic shock. Risk factors include malnutrition, alcohol use, gastrointestinal disease, and increased metabolic demand or losses, such as those seen with severe diarrhea. Critically ill patients, especially those with gastrointestinal losses, are at increased risk for thiamine deficiency, which can precipitate acute circulatory collapse and lactic acidosis.Clinical features of mixed (wet and dry) beriberi include high-output heart failure, pulmonary edema, hypotension, tachycardia, and encephalopathy, as described in the case. Diagnosis is often clinical, especially in the absence of specific tests, and a rapid response to thiamine supports the diagnosis. Imaging and laboratory findings may show hyperdynamic cardiac function, elevated lactate, and no clear infectious or structural cause.
Conclusions: This case emphasizes an important lesson: shock with pulmonary edema and hyperdynamic cardiac function should prompt consideration of thiamine deficiency, especially in patients with recent gastrointestinal illness or malnutrition. Early recognition is critical, as thiamine repletion is safe, inexpensive, and can be lifesaving.