Histoplasma capsulatum is the most common endemic mycosis worldwide. Although most of the globe's largest urban hubs fall outside this organism's regions of endemicity, clinicians practicing in a metropolis like New York City or Los Angeles must nevertheless remain vigilant for histoplasmosis because of the large immigrant population that is served by its hospitals. H. capsulatum infection ranges from asymptomatic pulmonary infection to life-threatening diffuse pneumonia with dissemination. The early years of the AIDS epidemic first introduced U.S. clinicians working in areas previously unfamiliar with histoplasmosis to newly immunocompromised patients from endemic regions presenting with disseminated H. capsulatum originally acquired in their home countries. Improvement in HIV prevention and therapeutics has reduced the frequency of such cases. Herein we report three cases of histoplasmosis encountered in our New York City institution over the last three years to emphasize that awareness of this infection remains mandatory for the frontline urban clinician.

This is a case report elucidating how severe hypothyroid-induced myopathy can lead to refractory kidney injury, unmanageable by standard medical and hemodialysis interventions. A 70-year-old female with extensive medical comorbidities including adult onset hypothyroidism, hypertension, hyperlipidemia, and normal baseline renal function presented with shortness of breath, myalgias, edema, and facial swelling. The patient was found to have a thyroid-stimulating hormone of 169.8 μIU/mL, creatine phosphokinase of 42,670 U/L, blood urea nitrogen of 70 mg/dL, a creatinine of 12.1 mg/dL, and glomerular filtration rate of 3 mL/min/1.73 m 2 . She was initiated on aggressive intravenous isotonic rehydration, along with intensive intravenous thyroid hormone replacement therapy and hydrocortisone treatment as well. Her renal status failed to improve adequately and she was started on sodium bicarbonate for urinary alkalinization. With the preceding interventions deemed medically futile for renal amelioration, the patient was started on acute hemodialysis. Over the course of 2 weeks and six hemodialysis treatments, the patient's renal status failed to improve. The patient finally refused any further hemodialysis or medical interventions seeing that her kidneys failed to respond to treatment, and her clinical prognosis remained poor. This case report illustrates how severe symptomatic hypothyroidism can induce rhabdomyolysis leading to intractable kidney failure, unmanageable by standard medical therapy and hemodialysis.