Hantaviruses are etiologic agents of hemorrhagic fever with renal syndrome, an acute illness characterized by acute renal insufficiency, proteinuria, and hemodynamic instability. Recently, a New World form of hantavirus disease, hantavirus pulmonary syndrome (HPS), was recognized; in this form, pulmonary edema is prominent, but renal insufficiency is generally lacking. HPS cases from the southeastern United States may be exceptional in that they have exhibited both pulmonary and renal manifestations. One case in Louisiana and one case in Florida were linked to infection by the distinct but closely related Bayou and Black Creek Canal hantaviruses, respectively. We report a nonfatal case of HPS caused by Bayou hantavirus that occurred in eastern Texas. Clinical manifestations included pulmonary and renal insufficiency and myositis, which had previously been observed in the patient from Florida. The occurrence of distinctive clinical abnormalities in HPS cases from the southeastern United States supports the concept that there are clinically significant differences between western and southeastern forms of HPS.