2025 – PAGE 328 – INFECTIOUS DISEASES
CYTOMEGALOVIRUS (CMV)
Cytomegalovirus (CMV) is generally benign in healthy individuals with symptoms similar to mononucleosis. Diagnosis in these healthy individuals can be made with IgM antibody in the acute phase. Intrauterine exposure, however, can cause severe problems. The classic triad is uni- or bilateral chorioretinitis, microcephaly, and periventricular intracerebral calcifications. Other possible findings include hearing loss, cognitive defects, seizures, thrombocytopenia (petechiae), and evidence of extramedullary hematopoiesis (hepatosplenomegaly and blueberry muffin rash). Diagnosis in neonates can be made by urine culture for CMV or PCR. Treat with Ganciclovir > Acyclovir to possibly prevent future hearing loss.
PEARLS: The hearing loss caused in kids with CMV is a sensorineural hearing loss. HIV patients may present with a CMV pneumonia. The calcifications in CMV are periventricular, and those of toxoplasmosis are diffuse.
MNEMONICS: Regarding Ganciclovir versus Acyclovir, try to associate CMV treatment with the G drug (G and C look very similar). Or “GCV for CMV?”
MNEMONIC: CMV = CCC! That should help you remember the classic triad of Chorioretinitis, Calcifications, and Censorineural hearing loss.
CONGENITAL HSV
Congenital HSV has a poor prognosis and is associated with high morbidity and mortality. A C-section should be done if the mother has active lesions. Breastfeeding should not be done if the mom has active lesions on her breast or other exposed lesions. Treat with IV acyclovir. If left untreated, 75% of those with localized disease will progress to CNS or disseminated infections. The disease is classified into 3 categories:
- Skin, Eyes, and Mouth (SEM) disease
- Central nervous system (CNS) disease +/- SEM
- Disseminated disease including the lungs, liver, adrenals + CNS + SEM
(DOUBLE TAKE) BLUEBERRY MUFFIN RASH DIFFERENTIAL DIAGNOSIS
Blueberry muffin rash represents extramedullary hematopoiesis. Differential diagnosis for blueberry muffin rash includes TORCH infections (including syphilis), hematologic disorders (hereditary spherocytosis, hematologic disease of the newborn, twin-to-twin transfusion), vascular disorders (like multiple hemangiomas) and malignancies (neuroblastoma, congenital rhabdomyosarcoma, Langerhans cell histiocytosis, congenital leukemia cutis).
IMAGE: www.pbrlinks.com/BLUEBERRY1
IMAGE: www.pbrlinks.com/BLUEBERRY2
ACUTE WATERY DIARRHEA
PEARLS: Acute watery diarrhea generally does not warrant a big workup or any testing unless you have concerns for specific organisms, like Clostridioides difficile, Cholera, or Giardia. NEVER choose a BRAT (bananas, rice, applesauce, and toast) diet as treatment. Always give an age-appropriate diet rather than prescribing bowel rest. This helps the GI mucosa stay as healthy as possible. When there is mild–moderate dehydration, a rehydration trial with Oral Rehydration Solution (ORS contains 2% glucose + 90 mEq NaCl) should be tried first. Stool studies that are positive for WBCs, neutrophils, mucous, or blood are more likely due to a BACTERIAL pathogen.
PEARL: For the pediatric certification exam, you should almost never pick loperamide! If it’s an organism that secretes toxins, stopping the diarrhea can be deadly. The one exception is traveler’s diarrhea.