2025 – PAGE 326 – INFECTIOUS DISEASES
TORCH INFECTIONS
NOTE: TORCH stands for Toxoplasma, Other (Varicella, Syphilis), Rubella, Cytomegalovirus (CMV), and Herpes Simplex Virus (HSV). Perinatal TORCH infections can lead to severe fetal anomalies and even death.
TOXOPLASMA GONDII
Toxoplasma gondii is a protozoan. Look for CNS and eye problems. The classic triad is diffuse intracerebral calcifications, hydrocephalus, and uni- or bilateral chorioretinitis. Other findings may include adenopathy, thrombocytopenia, hepatosplenomegaly, jaundice, and blueberry muffin rash. Toxoplasma is transmitted via cat litter. Diagnose by getting IgM titers or immunofluorescence. Treat with sulfadiazine or pyrimethamine.
PEARL: Just because a neonate looks good at birth does not mean you can cross this answer off in an older child. This can still present with seizures, cognitive issues, and even deafness.
PEARL: Toxoplasmosis can present exactly like CMV. A key differentiating factor is the IMAGING. The calcifications of toxoplasmosis are DIFFUSE and are referred to as “RING-ENHANCING LESIONS.” Those of CMV are PERIVENTRICULAR and do not enhance.
(DOUBLE TAKE) VARICELLA ZOSTER VIRUS (CHICKEN POX)
The varicella zoster virus causes CHICKEN POX. A chicken pox lesion may be described as a “dew drop on a petal” during the vesicle phase. Lesions are said to come in “crops” at different times, and will therefore appear in different stages on the body (some vesicles, some crusted lesions). The rash goes to the TRUNK and then to the FACE and EXTREMITIES. It lasts for 7–10 days and leaves minimal scars. Congenital Varicella Syndrome (CVS) may present with scars from the intrauterine infection, limb hypoplasia, ocular defects (e.g., chorioretinitis, microphthalmia, cataracts), neurologic issues (e.g., microcephaly, seizures, developmental delays), and low birth weight.
PEARL: VZIG (VZV immunoglobulin) is given for prophylaxis to newborns if the mom developed symptoms within FIVE days prior to delivery and TWO days after delivery. If symptoms started six days prior to delivery, then chances of vertical transmission are low and NO PROPHYLAXIS IS NEEDED. Congenital varicella syndrome can result in low birth weight as well as CNS, eye and skin abnormalities.
PEARL: Any immunocompromised patient should avoid contact with patients who have a case of the chicken pox.
NOTE: It’s doubtful you will need to know about the smallpox virus (Variola). In case you do, just know that the lesions all appear at the SAME TIME, so all lesions will look similar. Other facts include –> limited to face/extremities, lasts up to 3–4 weeks and leaves lots of scarring.
(DOUBLE TAKE) MNEMONIC: Imagine a patient who is bored because he’s stuck in a NEGATIVE PRESSURE ISOLATION room, and the only channel he gets to watch is MTV. Negative pressure isolation is required for Measles, Mycobacterium Tuberculosis and Varicella. As mentioned in the Aspergillus section, that, too, requires negative pressure isolation.
(DOUBLE TAKE) SYPHILIS
Syphilis is caused by TREPONEMA PALLIDUM. Non-treponemal tests (RPR or VDRL) can be FALSE positives, so you need to do a confirmatory treponemal test (FTA). While the FTA does not correlate with disease activity, the non-treponemal tests do. Also, the non-treponemal tests may eventually disappear with decreased disease activity. So once disease presence is confirmed with FTA, look at disease activity with non-treponemal titers to help guide management. Neonates born to a mother with a reactive non-treponemal (RPR or VDRL) test result should have a quantitative non-treponemal serologic test (RPR or VDRL) performed on the infant’s serum. Treponemal serologic tests (FTA) on a baby are difficult to interpret so are not recommended. An immunoglobulin (IgM) test is also not currently available. If the mom was treated and the baby’s titers are lower than hers, it’s safe to assume that those are just the mom’s IgGs that crossed the placenta and that there is NO NEED TO TREAT (just follow the titers). If the mom was treated < 1 month ago, TREAT. If the mom was given Erythromycin, TREAT because it doesn’t cross the placenta.
- CONGENITAL SYPHILIS: The baby can be born with a maculopapular rash, HSM, generalized lymphadenopathy and PEELING SKIN. If left untreated, the baby may later develop a PERFORATED PALATE, a PERFORATED NASAL SEPTUM, hearing loss, HUTCHINSON TEETH or a host of other complications. Hutchinson teeth are peg-shaped (cone-like) but also have a central notch that is extremely specific for congenital syphilis. Treat with PENICILLIN (PCN).
- CONDYLOMA LATA refers to SECONDARY SYPHILIS, in which white-gray coalescing papules are seen.
- PEARL: If the FTA is positive but VDRL is negative, also consider LYME DISEASE (BORRELIA BURGDORFERI).
- NAME ALERT/MNEMONIC: Condyloma LATA (AKA “condyloma FLATa,” are much more FLAT than Condyloma ACUMINATA (which is found with HPV infections).
- NAME ALERT/MNEMONIC: Peg teeth are also found in patients with Incontinentia Pigmenti (AKA “incontinentia PEGmentia”).
- IMAGE: (PEG-SHAPED TEETH) – www.pbrlinks.com/PEGTEETH1
- IMAGE: (HUTCHINSON TEETH) – www.pbrlinks.com/HUTCHTEETH1