Recurrent Infections

A person who has an infection with the same organism in the same anatomic location multiple times can become very frustrated. The physician must determine the underlying cause, in order to prevent recurrence.The medical history will often point to the source of the infection.

For example:

Several episodes of pneumococcal meningitis occurring in a 30-year old male with a history of head trauma should alert the physician to a possible anatomic brain defect. Computerized axial tomography (CT scan) of the head with images from the front of the face to the back of the head (coronal cuts), instead of standard images from the top of the head to below the chin may reveal a cerebrospinal fluid (CSF) fistula. Surgery repairs the leak.

Multiple episodes of Klebsiella pneumoniae bloodstream infection in a 40-year-old male who stepped on a nail should suggest a foreign body. A puncture through the sole of a shoe into the foot can cause retention of rubber or fibers in the wound. Surgical exploration of the wound determines if threads from a sock serve as a nidus of infection. Removal of all fibers prevents further infection.

Not only is streptococcal cellulitis of the right leg of a 70-year-old male a known complication of saphenous vein harvesting for a coronary artery bypass graft (CABG), but also repeated infections occur due to the altered anatomy. Patients who have two or more episodes of cellulitis per year require prophylactic antibiotics and may need them permanently.

Several episodes of urinary tract infection in a 60-year-old female who had an ileo-uretero diversion for bladder cancer should trigger an evaluation. Ultrasound of the kidneys may show a perinephric abscess, a complication of repeated urinary tract infections with obstruction, or, in this case, altered urinary tract anatomy. Needle aspiration of the abscess under ultrasound guidance prevents further episodes.

Recurrent episodes of pain in the left cheek and teeth accompanied by pus draining from the mouth in a 13-year old boy requires an evaluation. CT scan of the head may show an extra tooth embedded in a sinus. Endoscopic surgery removes the tooth and resolves the infection.

Repeated elevations of white blood cells with no bacteria seen in a urine sample (sterile pyuria) can have a number of causes, not only a partially treated urinary tract infection, but also a classic sign of genitourinary tuberculosis.

Repeated infections can cause a patient to undergo multiple courses of intravenous antibiotics with multiple hospitalizations. A careful history may lead to the correct diagnosis.