A 41-year-old human immunodeficiency virus (HIV)-positive man was hospitalized with complaints of a 4-week history of nausea and vomiting, associated with decreased oral intake, and a 4-day history of frontal headache and fever. His medical history was significant for a gunshot wound to the head 3 years prior, with a residual seizure disorder. He also had two previous hospitalizations, both for culture-negative bacterial meningitis; the first episode occurred 12 months before admission and the second episode occurred 5 months later. At that time, he was found to be positive for serum antibodies against HIV and a CD4+ T-lymphocyte count of 126/mm3. He had no known drug allergies and was not receiving any medication. On admission, the patient was febrile (104.0 degrees F) and hypotensive (blood pressure, 92/40 mm Hg). Pertinent physical examination findings included cachexia with bitemporal wasting, dry mucus membranes, adherent white patches on the oral mucosa, and negative Kernig's and Brudzinski's signs. His laboratory results revealed macrocytic anemia, a decreased serum sodium of 125 mEq/L, and a normal total leukocyte count with a CD4+ T-lymphocyte count < 50/mm3. Lumbar puncture opening pressure was elevated at 160 mm Hg, and cerebrospinal fluid analysis showed an increased white cell count of 97/microL (84% lymphocytes), a decreased glucose level of 26 mg/dL, and a decreased protein level of 42 mg/dL. The patient was started on empiric therapy that included intravenous ampicillin and cefotaxime, oral Bactrim, and clotrimazole lozenges for thrush. Cerebrospinal fluid culture was positive for Escherichia coli, sensitive to cefotaxime. Two days later, the patient developed fine, erythematous, nonblanchable macules primarily on his abdomen, with minimal involvement of his thorax and back. His skin lesions remained unchanged for the next 2 weeks. Repeat lumbar puncture was performed after 14 days of cefotaxime. The cerebrospinal fluid analysis showed an elevated white cell count of 7/microL (100% lymphocytes), a decreased glucose level of 53 mg/dL, and a decreased protein level of 33 mg/dL. The cerebrospinal fluid culture was now positive for Pseudomonas aeruginosa resistant to cefotaxime. The patient was started on imipenem. On day 34 of his admission, the patient became tachypneic with complaints of dyspnea. A chest roentgenogram revealed bilateral patchy infiltrates. He was transferred to the intensive care unit and intubated for hypoxemic respiratory failure (arterial blood gas values on 6 L of oxygen: pH, 7.46; bicarbonate, 23; and oxygen saturation, 37). That evening, the patient was also noted to have diffuse petechiae and purpura in a reticulated pattern over his abdomen (Figure 1A and 1B), most heavily concentrated in the periumbilical region, extending to the axillae and upper thighs. A 3x3-mm punch biopsy from abdominal skin demonstrated Strongyloides stercoralis larvae in the dermis (Figure 2A and 2B). His sputum specimen was teeming with adult S stercoralis worms (Figure 3) and, subsequently, numerous S stercoralis larvae were observed not only from the bronchoalveolar lavage but also from the nasogastric fluid specimen. These findings confirmed the diagnosis of disseminated strongyloidiasis. On hospital day 35, the patient was doing poorly and was started on thiabendazole (1250 mg twice daily for 28 days). Nine days later, ivermectin (4.5 mg once daily for 3 days for 2 courses) was also added. He continued to clinically deteriorate. The patient died 31 days after systemic antihelminthic treatment was initiated.