9260_chapter11 6/13/05 12:27 PM Page 415 EXAM Fever, CVA tenderness, mild abdominal tenderness. DIFFERENTIAL Renal stones, renal infarcts, cholecystitis, appendicitis, diverticulitis, acute prostatitis/epididymitis. DIAGNOSIS UA shows pyuria and bacteriuria and may also exhibit hematuria or WBC casts. CBC reveals leukocytosis with left shift. Urine culture is usually positive, and blood culture may be positive as well. в– are seen in pyelonephritis but not in cystitis. TREATMENT в– Fever and WBC casts on UA Fluoroquinolone Г— 7 days or ampicillin + gentamicin or ceftriaxone Г— 14 days. Radiologic evaluation for complications may be useful in patients who are severely ill or immunocompromised, who are not responding to treatment, or in whom complications are likely (e.g., pregnant patients, diabetics, and those with nephrolithiasis, reflux, transplant surgery, or other GU surgery). в– X-rays can detect stones, calcification, masses, and abnormal gas collections. в– Ultrasound is rapid and safe. в– Contrast-enhanced CT is most sensitive but may affect renal function. COMPLICATIONS I N FECTIOUS DISEASES Perinephric abscess should be considered in patients who remain febrile 2вЂ“3 days after appropriate antibiotics; UA may be normal and cultures negative. Patients are treated by percutaneous or surgical drainage plus antibiotics. Intrarenal abscesses (e.g., infection of a renal cyst) < 5 cm in size usually respond to antibiotics alone. Diabetics may develop emphysematous pyelonephritis, which usually requires nephrectomy and is associated with a high mortality rate. R O C K Y M O U N TA I N S P OT T E D F E V E R A tick-borne illness caused by Rickettsia rickettsii. The vector is the Dermacentor tick, which needs to feed for only 6вЂ“10 hours before injecting the organism (a much shorter attachment time than for Lyme disease). Most commonly occurs in the mid-Atlantic and South Central states (not the Rocky Mountain states). The highest rates are seen in late spring and summer and in children and men with occupational tick exposures. Think of Rocky Mountain SYMPTOMS/EXAM в– в– в– Initial symptoms (seven days after a tick bite): Fever, myalgias, and headaches. Maculopapular rash (in 90%) starts four days later and progresses to petechiae or purpura. The rash first appears on the wrists and ankles and then spreads centrally and to the palms and soles. Patients may develop severe headache, irritability, and even delirium or coma. spotted fever and start treatment early in patients with a recent tick bite (especially in the mid-Atlantic or South Central states) along with fever, headache, and myalgias followed by a DIFFERENTIAL Meningococcemia, measles, typhoid fever, ehrlichiosis (HME or HGE), viral hemorrhagic fevers (e.g., dengue), leptospirosis, vasculitis. 415 centripetal rash.