Lumbar puncture in the evaluation of possible asymptomatic congenital syphilis in neonates

Congenital Syphilis: A U.S. Perspective

Congenital syphilis still represents a worldwide public health problem. If left untreated, it can lead to fetal demise and high neonatal morbidity and mortality. Unfortunately, in the last decade, there has been a resurgence of cases in the U.S. This review discusses the ongoing problem of this preventable congenital infection, vertical transmission and clinical manifestations while providing a guidance for the evaluation and management of infants born to mothers with reactive serologic tests for syphilis.

Syphilis in Children

Syphilis, caused by Treponema pallidum, is transmitted both sexually and transplacentally. Untreated syphilis is a progressive disease that may result in death or disability in children and adults. Syphilis diagnosis requires 2-stage serologic testing for nontreponemal and treponemal antibodies. Congenital syphilis diagnosis requires careful review of maternal testing and treatment, comparison of maternal and neonatal nontreponemal antibody titers, and clinical evaluation of the neonate. In this review, we present the current epidemiology of syphilis, and the clinical manifestations, diagnosis, and management of syphilis as they relate to pediatric practice, specifically, congenital syphilis and acquired syphilis in adolescents and pregnant women.

Evaluation of the management of pregnancies and infants at risk for congenital syphilis: La Réunion, 2008 to 2014

OBJECTIVE

To evaluate the maternal-fetal management and follow-up of infants at risk for congenital syphilis.

STUDY DESIGN

Monocentric retrospective cohort study at the Félix Guyon Hospital, Saint-Denis, La Réunion between January 2008 and December 2014. Management of 38 pregnancies (35 women, 39 fetuses) with a positive syphilis serology was evaluated according to the Centers for Disease Control and Prevention (CDC) guidelines.

RESULTS

A total of 68% (n=26) of pregnancies were screened before 16 weeks of gestation, and 26% (n=10) had appropriate treatment. Adverse outcomes were noted in 45% of pregnancies. Neonatal serology was not performed in 7 live-born neonates (19%) and 33 infants were classifiable according to the four CDC scenarios. In the infants, adequate complementary evaluation and appropriate treatment were noted in 42% (n=13) and 55% (n=17) of cases, respectively. Rate of infant follow-up was 76% (n=16). No treatment failure was observed in infants.

CONCLUSION

Reinforcement of public health policies and a better sensitization, training and collaboration among perinatal caregivers are warranted given the gaps revealed in our study.

Canadian Public Health Laboratory Network laboratory guidelines for congenital syphilis and syphilis screening in pregnant women in Canada

Despite universal access to screening for syphilis in all pregnant women in Canada, cases of congenital syphilis have been reported in recent years in areas experiencing a resurgence of infectious syphilis in heterosexual partnerships. Antenatal screening in the first trimester continues to be important and should be repeated at 28 to 32 weeks and again at delivery in women at high risk of acquiring syphilis. The diagnosis of congenital syphilis is complex and is based on a combination of maternal history and clinical and laboratory criteria in both mother and infant. Serologic tests for syphilis remain important in the diagnosis of congenital syphilis and are complicated by the passive transfer of maternal antibodies which can affect the interpretation of reactive serologic tests in the infant. All infants born to mothers with reactive syphilis tests should have nontreponemal tests (NTT) and treponemal tests (TT) performed in parallel with the mother's tests. A fourfold or higher titre in the NTT in the infant at delivery is strongly suggestive of congenital infection but the absence of a fourfold or greater NTT titre does not exclude congenital infection. IgM tests for syphilis are not currently available in Canada and are not recommended due to poor performance. Other evaluation in the newborn infant may include long bone radiographs and cerebrospinal fluid tests but all suspect cases should be managed in conjunction with sexually transmitted infection and/or pediatric experts.

Congenital syphilis: still a serious, under-diagnosed threat for children in resource-poor countries

BACKGROUND

With 700,000 to 1.5 million new cases annually, congenital syphilis remains a major infectious cause of morbidity and mortality in neonates, infants and children in resource-poor countries. We therefore analyzed the extent of congenital syphilis in the pediatric patient population at our rural hospital in Tanzania.

METHODS

For this retrospective analysis, from January 1, 1998 to August 31, 2000, all cases of congenital syphilis were collected from the medical records of the neonatal and pediatric department at Haydom Lutheran Hospital in rural northern Tanzania. Age, sex, weight, clinical signs and symptoms, venereal disease research laboratory (VDRL) results of mother and/or child, hemoglobin concentration, treatment, and outcome were recorded and analyzed.

RESULTS

Fourteen neonates and infants were included. The earlier the diagnosis, the more it rested on maternal data because the presentation of neonatal congenital syphilis resembled neonatal sepsis. Syphilitic skin lesions were only seen in the post-neonatal age group. VDRL results were positive in 11 of the 14 mothers, and in 4 of the infants. Anemia was common in older infants. No patient showed signs of central nervous system involvement. Two patients died, and the remaining were cured after standard treatment with procaine penicillin.

CONCLUSIONS

Highlighting the variable picture of congenital syphilis, this report demonstrates how difficult it is to make a correct diagnosis by solely history and clinical presentation in a resource-poor setting. Hence false-positive and false-negative diagnoses are common, and clinicians have to maintain a high index of suspicion in diagnosing congenital syphilis. Therefore, an important approach to control and finally eliminate congenital syphilis as a major public health problem will be universal on-site syphilis screening of all pregnant women at their first antenatal visit and immediate treatment for those who test positive.

Analysis of cerebrospinal fluid in the neonate

NEONATES PRESENTING WITH apnea, seizures, signs and symptoms of infection or neurologic disorders often require evaluation of cerebrospinal fluid (CSF) as part of their diagnostic workup. Multiple studies can be done on CSF, including, but not limited to, evaluation of color, bacterial culture and Gram’s stain, viral culture, cell count and differential, polymerase chain reaction (PCR), and quantitative determination of a number of laboratory values. Proper evaluation of CSF depends on knowing which tests to order, normal ranges for the patient’s age, and the limitations of the test.1 Reference ranges for CSF studies have been well established in the adult, but are not as well defined in the neonatal population.2,3 This situation is further complicated by the vast differences between preterm and term infants. This column covers the interpretation of the most common tests done on CSF in the neonate. Many of the references cited are more than ten years old, but little new data support changes in the interpretation of neonatal CSF studies.

Congenital syphilis: beta2-microglobulin in cerebrospinal fluid and diagnosis of neurosyphilis in an affected newborn

Meningoencephalitis in neonatal congenital syphilis (CS) is a difficult diagnosis because of the limitation of standard cerebrospinal fluid (CSF) tests. This limitation means that new markers in CSF tests are needed to establish whether meningitis is present in presumptive cases of CS. beta2-Microglobulin (beta2-m) is raised in CSF recovered from neonates with central nervous system (CNS) infections, but it does not correlate with cellular count or proteins in the CSF. We present a preterm newborn with symptomatic CS. First-day CSF showed 50 cells/mm3, protein of 220 mg/dL and a beta2-m concentration of 16.9 mg/dL (normal <2.25 mg/dL). Serial determinations of beta2-m showed a marked reduction (76%) after 10 days of appropriate treatment. At 30 days of life, beta2-m was already within the normal range (1.8 mg/dL). Cerebral ultrasonography showed ventricular dilatation, moderate periventricular echogenicity, subependimal hemorrhages, and linear hyperechoic areas in the thalamus and basal ganglia. We suggest that beta2-microglobulin is very useful in the diagnosis of CNS involvement and in monitoring the response to treatment. In addition, infants with CS may exhibit CNS imaging findings similar to those observed in other intrauterine CNS infections.

Central nervous system infection in congenital syphilis

BACKGROUND

Identification of infants with Treponema pallidum infection of the central nervous system remains challenging.

METHODS

We used rabbit-infectivity testing of the cerebrospinal fluid to detect T. pallidum infection of the central nervous system in infants born to mothers with syphilis. The results were compared with those of clinical, radiographic, and conventional laboratory evaluations; IgM immunoblotting of serum and cerebrospinal fluid; polymerase-chain-reaction (PCR) assay testing of serum or blood and cerebrospinal fluid; and rabbit-infectivity testing of serum or blood.

RESULTS

Spirochetes were detected in the cerebrospinal fluid of 19 of 148 infants by rabbit-infectivity testing. Exposure of the infant to antibiotics before cerebrospinal fluid was obtained for rabbit-infectivity testing was associated with a negative test result (P=0.001). Spirochetes were detected in the cerebrospinal fluid in 17 of 76 infants (22 percent) who had no prior antibiotic exposure. These 17 infants included 41 percent (16 of 39) of those with some abnormality on clinical, laboratory, or radiographic evaluation; 60 percent (15 of 25) of those with abnormal findings on physical examination that were consistent with congenital syphilis; and 41 percent (17 of 41) of those with a positive result on IgM immunoblotting or PCR testing of serum, blood, or cerebrospinal fluid, or a positive result on rabbit-infectivity testing of serum or blood. Only one infant who had normal findings on clinical evaluation had a positive cerebrospinal fluid rabbit-infectivity test. Overall, central nervous system infection was best predicted by IgM immunoblotting of serum or PCR assay of serum or blood.

CONCLUSIONS

Most infants with T. pallidum infection of the central nervous system can be identified by physical examination, conventional laboratory tests, and radiographic studies. However, the identification of all such infants requires the use of additional tests, including IgM immunoblotting and PCR assay.

Problems in the current case definitions of congenital syphilis

During the course of a population-based epidemiologic study of congenital syphilis, we found discrepancies and problems of validity in the case definitions of congenital syphilis of the Centers for Disease Control and Prevention and other experts. We analyzed these problems and determined their impact on case classification in our study. The most important problem that we found was the case definitions' lack of a valid scientific basis for the classification of symptom-free infants born to mothers who have been treated for syphilis but have uncertain infection status (286 infants in our study). The classification of these infants is based on diagnostic tests whose sensitivity and specificity are unknown. In our study, we found that results of some tests were rarely positive and that values for others were similar to those in uninfected infants. We believe that symptom-free infants of treated mothers of uncertain infection status should be classified as cases, pending the development of better diagnostic tests for congenital syphilis. The economic impact of treating these infants can be lessened by obtaining fewer diagnostic tests and by use of one injection of penicillin rather than a 10- to 14-day course, an approach suggested by a literature review. Use of infants' diagnostic tests to classify any other group of symptom-free infants does not seem appropriate, even though this is often recommended.