Diagnostic tests. Maternal diagnosis is dependent upon knowing the results of both a nontreponemal (RPR, VDRL) and a confirmatory treponemal test (TP-PA, TP-EIA, TP-CIA, FTA-ABS,) before or at delivery. TP-PA is the preferred test. When maternal disease is confirmed, the newborn should have the same quantitative nontreponemal test as the mother. A confirmatory treponemal test is not required
Evaluation and treatment. It’s imperative that children born to mothers with a reactive test, regardless of their treatment status, have a thorough exam performed before hospital discharge. The provider must determine what additional interventions should be performed.
The American Academy of Pediatrics and the Centers for Disease Control and Prevention (www.cdc.gov/std/treatment-guidelines/congenital-syphilis.htm) have developed standard algorithms for the diagnostic approach and treatment of infants born to mothers with reactive serologic tests for syphilis. It is available in the Red Book for AAP members (https://publications.aap.org/redbook). Recommendations based on various scenarios for neonates up to 1 month of age include proven or highly probable congenital syphilis, possible congenital syphilis, congenital syphilis less likely, and congenital syphilis unlikely. It is beyond the scope of this article to list the criteria and evaluation for each scenario. The reader is referred to the algorithm.
If syphilis is suspected in infants or children older than 1 month, the challenge is to determine if it is untreated congenital syphilis or acquired syphilis. Maternal syphilis status should be determined. Evaluation for congenital syphilis in this age group includes CSF analysis for VDRL, cell count and protein, CBC with differential and platelets, hepatic panel, abdominal ultrasound, long-bone radiographs, chest radiograph, neuroimaging, auditory brain stem response, and HIV testing.
Let’s go back to your patient. The mother was diagnosed with syphilis during pregnancy. You confirm that she was treated with benzathine penicillin G, and the course was completed at least 4 weeks before delivery. Treatment with any other drug during pregnancy is not appropriate. The RPR has declined, and the infant’s titer is equal to or less than four times the maternal titer. The exam is significant for generalized adenopathy and slightly bloody nasal discharge. This infant has two findings consistent with congenital syphilis regardless of RPR titer or treatment status. This places him in the proven or highly probable congenital syphilis group. Management includes CSF analysis (VDRL, cell count, and protein), CBC with differential and platelet count, and treatment with penicillin G for 10 days. Additional tests as clinically indicated include: long-bone radiograph, chest radiography, aspartate aminotranferase and alanine aminotransferase levels, neuroimaging, ophthalmologic exam, and auditory brain stem response. Despite maternal treatment, this newborn has congenital syphilis. The same nontreponemal test should be obtained every 2-3 months until it is nonreactive. It should be nonreactive by 6 months. If the infection persists to 6-12 months post treatment, reevaluation including CSF analysis and retreatment may be indicated.
Congenital syphilis can be prevented by maternal screening, diagnosis, and treatment. When that fails it is up to us to diagnosis and adequately treat our patients.
Dr. Word is a pediatric infectious disease specialist and director of the Houston Travel Medicine Clinic. She said she had no relevant financial disclosures. Email her at pdnews@mdedge.com.