2025 – PAGE 325 – INFECTIOUS DISEASES

CHOLESTEATOMA

A cholesteatoma results in PAINLESS otorrhea due to a DESTRUCTIVE lesion at the base of the skull. This can be associated with, or lead to, hearing loss. It can erode important structures. Otorrhea will include debris containing SKIN and EPITHELIAL cells. Landmarks on otoscopic examination may be absent due to destruction. Treatment requires excision of the lesion.

CHRONIC OTORRHEA AND RECURRING OTORRHEA

The most common causes of chronic otorrhea and recurring otorrhea are PSEUDOMONAS and STAPH. Give OFLOXACIN DROPS.

PEARL: This may give a similar presentation to cholesteatoma, but there should be NO skin or epithelial debris. Also, consider the presence of a concurrent cholesteatoma if it’s not improving with appropriate anti­biotics.

MNEMONIC: The most common bugs are not the HMS bugs. They are the same as the otitis externa bugs—maybe because of the connection to the outside world?

MENINGITIS, BACTERIAL AND VIRAL

If you suspect meningitis (unexplained fever, irritability, lethargy) in a patient with NO FOCAL DEFICITS, go straight for the lumbar puncture without waiting for the CT. If there is focality, give immediate antibiotics followed by a CT and then an LP.

• BACTERIAL MENINGITIS: Look for an elevated protein and a low glucose (< 40, or less than 2/3 the serum glucose). Look for a predominance of neutrophils in the CSF. The number of leukocytes should be > 100, but hopefully the board of pediatrics will be kind enough to provide one in the THOUSANDS.
  • AGE < 30 DAYS: Ampicillin and gentamicin. The ampicillin covers Listeria.
  • AGE 1–3 MONTHS: Consider changing over to vancomycin and ceftriaxone.
  • AGE > 3 MONTHS: Definitely give vancomycin and ceftriaxone.
  • (DOUBLE TAKE) PEARL: Ceftriaxone is still great for Streptococcus. When treating for meningitis, also give Vancomycin. The vancomycin is NOT being given for Staph aureus coverage. It’s being given for possible Strep that is RESISTANT to ceftriaxone!
• VIRAL MENINGITIS: This will show a low WBC count (< 500) and should have a lymphocyte predomi­nance. The CSF glucose level will be normal. The CSF protein level should be normal or slightly elevated. If there is concern for HSV encephalitis, START ACYCLOVIR.
  • PEARL: MENINGITIS + SEIZURE = IMMEDIATE ACYCLOVIR. Assume it’s due to HSV, even if the CSF is 100% suggestive of a bacterial meningitis. Give antibacterial antibiotics as well. Send the CSF for HSV PCR to diagnose.
  • PEARL: WBCs do NOT belong in the CSF. If there are ANY, there’s something going on. If it’s due to a traumatic tap, then assume that 1 WBC is present for every 500 to 1000 RBCs. So if a patient has a traumatic lumbar puncture which shows 10,000 RBCs and 130 WBCs, you should assume there are over 100 extra WBCs!
  • PEARL: Since meningitis can cause hearing loss, do a hearing screen as soon as possible, ideally before hospital discharge.