Building a Diagnosis from the Ground Up

A CLINICAL PROBLEM-SOLVING article by Brook Watts from Louis Stokes Cleveland VA Medical Center in Ohio.
A 49-year-old man came to the clinic with a 1-week history of suprapubic pain and fever. On examination, he had a temperature of 38.1°C but appeared well. A urinalysis revealed numerous white cells, two red cells, and more than two bacteria per high-power field. A urinary tract infection was diagnosed, and oral gatifloxacin was prescribed.
The patient returned the following day, reporting an inability to urinate and he was discharged home with an indwelling urinary catheter and a prescription for oral doxazosin.
The patient's symptoms persisted and he returned 3 days later. CT of the abdomen and pelvis revealed an abscess in the right portion of the prostate gland. In addition, in the normal location of the spleen, contrast-enhanced CT showed a 4-cm soft-tissue density that was thought to be a hypoplastic or accessory spleen.
On admission, the patient reported new pruritic lesions on his arms, face, and trunk and pain in his right ankle. The patient worked as a long-distance bus driver. His normal routes were through the midwestern and northeastern United States.
The patient's condition declined and he was eventually intubated and placed on ventilatory support.
What could explain multiple nodular and pustular skin lesions, a prostatic abscess, mild fever, monoarticular joint involvement and subsequent physiologic decline? In this case, the correct diagnosis was reached only by building from the ground up, one clue at a time.

Blastomyces dermatitidis感染によるブラストミセス症。ミシシッピ川流域を侵淫する風土病。