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Diagnostic Problems in Early Congenital Syphilis

 Rediger
 1 Published: 18.11.04 Updated: 18.11.2004 15:31:10
Victoria Mironova1, Victor Bas2, Vladimir Massiouk3
Republic Infectious Hospital1, Republic Dermatological and Venereal Diseases Dispensary2, Center of State Sanitary and Epidemiological Control, Karelian Republic3
In this article we discuss problems concerning the overdiagnosis of congenital syphilis because of the presence of placentally transferred maternal antibodies in the newborns. We present the data on 36 babies born to mothers who had syphilis at the time of birth. The dynamics of serological reactions were followed and compared with sereological results of the mother. Each congenital syphilis was diagnosed in six children. Children need to be thoroughly examined to exclude the possibility of other intrauterine infections. Examination for the identification for congenital syphilis was diagnosed in six children. Examination for the identification of congenital syphilis should be comprehensive and dynamic in order to avoid overdiagnosis.

Introduction

The increasing spread of syphilis in Russia during the last decade has led to an increasing incidence of early congenital syphilis. The appearance of congenital syphilis signals inadequate preventive measures among pregnant women.

The pathogenesis of early congenital syphilis depends on the fetal immune response and to a minor extent on the cyto-destructive effect of Treponema pallidum. It is assumed that the fetus is not mature enough to produce antibodies to the foreign antigen before the 16th week of pregnancy (1). Thus the provision of adequate treatment for the mother before 16-19 weeks gestation can prevent fetal lesions (1).

Maternal antibodies transferred through the placenta can cause difficulties in the diagnosis of early congenital syphilis (1,2,5). Three to four months after delivery maternal antibodies are destroyed, and previously positive serological reactions caused by the maternal antibodies become negative. A positive serological reaction that persists after 3-6 months of birth indicates early congenital syphilis.

In the Karelian Republic in 1999, there were 73 children born to mothers who had been ill with syphilis. Among these children, 22 cases of early congenital syphilis were diagnosed at birth by our department. By the age of 3-4 months their serological reactions became negative indicating that the initial positive reactions reflected maternal antibodies. Taking these experiences into account we try to avoid overdiagnosing congenital syphilis.

Materials and Methods

We analysed data on 36 children whose mothers were ill with syphilis between January 1 and June 1, 2000. Excluding two children who were admitted at a later date, the children were transferred from maternity homes in Karelia to the Department of Republic Infectious Disease Hospital between five and ten days after birth for examination and diagnosis of early congenital syphilis.

The comprehensive examination included examination by an otorhinolaryngologist, opthalmologist and neuropathologist, radiography of limbs, and blood and cerebrospinal fluid examination for syphilis (ELISA with aggregated antigens, ELISA IgM, passive hemagglutination reaction, fluorescent treponemal antibody test (FTA–200, FTA-ABS and FTA–C), Treponema pallidum immobilization reaction). Serological tests were taken upon admission and after the completion of antibacterial treatment. Twenty-seven children stayed in the department with their mothers who also were examined for further comparison of serological reactions.

All children received treatment. Children with confirmed early congenital syphilis underwent a 14-day course of penicillin therapy. The other children received preventive intramuscular penicillin treatment or extencillin treatment for 10 days.

Results

Early congenital syphilis was identified in six out of 36 investigated children. The following data were collected among the mothers (table 1): 16 were ill with syphilis before pregnancy (13 as long as two years prior), 16 women had syphilis identified during pregnancy (in eight cases after eight weeks of pregnancy); nine women had been provided with the corresponding specific treatment including the preventive maternal course, but six women did not complete the course due to various problems. In five cases the disease was identified only after delivery and the mothers received postnatal treatment. Among those who had syphilis in their history five women did not receive preventive treatment as two years had elapsed since their illness.

Table 1. Early congenital syphilis in 36 children born to women with syphilis

Syphilis first identified in mother

Treatment of mothers

State of children

Specific

Maternal

course

Healthy

Sick

Before pregnancy

16

16

11

16

0

During pregnancy

15

15

9

14

1*

After delivery

5

0

0

0

5

* a pregnant woman had just completed treatment for secondary syphilis before the delivery

The contact group consisted of 30 children born at full term. Hypertrophy  (≤2800 g) was identified in 19 cases and was associated with the mother’s pathology: eight cases of chronic fetoplacental insufficiency, six of anemia, four of chronic respiratory infections, two of herpetic infection, two of chlamydia, one case of active tuberculosis, and two cases of chronic hepatitis C. Another intrauterine infection of unspecified etiology was identified in six babies from this group including four children who had liver lesions, one who had lesions of the central nervous system and one who had renal pathology. Two babies had evidence of hepatitis C infection. There was no otorhinolaringologic pathology or anemia from birth among this group of children. A reduction of hemoglobin and erythrocytes in peripheral blood associated with intrauterine infection was observed in six babies. Bone alterations were identified by X-ray in 12 cases (seven cases with initial symptoms of osteochondritis and five cases of first-degree osteochondritis). We do not consider isolated first-degree osteochondritis to be a specific symptom of early congenital syphilis.  Changes in the fundus of the eye were observed rather frequently. During the first week of life 12 cases of retinopathy were diagnosed. However, following repeated examination the diagnosis was changed to chorioretinitis by the second or third week in four cases. Three children had negative serological reactions while the other children had positive rections. Fifteen children had titres at the same levels as their mother and 12 had titres lower than their mother. All of the children had negative ELISA IgM. Lumbar puncture was performed on 28 children. Routine investigation of the cerebrospinal fluid was normal. All of the contact children had negative syphilis tests in the cerebrospinal fluid (ELISA, micro reaction, passive hemagglutination reaction).
In the absence of other clinical indications of syphilis, positive blood serological reactions were considered to be the result of transplacental transfer of maternal antibodies. In doubtful cases with high titres, preventive treatment was provided in a dose similar to that given for confirmed early congenital syphilis. The child was observed and a final diagnosis was made at the age of three months. Serological reactions among the children of this group became negative at the age of 3-4 months.
Six babies had early congenital syphilis diagnosed. These cases developed because the mothers had received no specific treatment at all (five cases) or treatment was provided too late (one case). Of the six women, four had secondary recurrent syphilis, one had secondary acute syphilis, and one woman had early latent syphilis. It is believed that mothers with untreated secondary syphilis can infect the fetus (3), and our data support this observation. In this group all babies were born full term. Two babies were small for gestational age. The following specific symptoms were identified: Two cases of first-degree osteochondritis and two cases of chorioretinitis («salt and pepper»). Symptoms that are not considered to be specific were also taken into account: three cases of hepatomegalia, six cases of intracranial hypertension, and four cases of spastic paraparesis. In two children syphilitic hepatitis with positive dynamics at the onset of antibiotic therapy were identified. In two cases, co-infection with hepatitis C virus was identified (HCV IgM positive). Serum reactions of all children with early congenital syphilis were positive in high titres, Treponema pallidum immobilisation reaction was 75–87% and ELISA IgM was positive in two cases. Investigation of the cerebrospinal fluid showed cell numbers and protein concentrations within normal limits. Positive serum reactions of cerebrospinial fluid were as follows: passive hemagglutination reaction – 1, micro reaction  – 1, ELISA  – 1, FTA-C  – 6 (indexes 3-4+).

Discussion

The medical service has developed a comprehensive plan for the prevention of early congenital syphilis. Mothers who have undergone adequate specific and preventive (maternal course) treatment give birth to healthy children. Untreated women can also have healthy children depending on the stage of the mother’s illness.
Early identification of syphilis especially among the pregnant, timely and adequate treatment as well as preventive treatment of children according to indications is important in the prevention of congenital syphilis. 

A comprehensive approach including the mother’s history, clinical data and the determination of the mother’s and baby’s serological reactions (including changes over time) is required in diagnostics. The main difficulties that we experienced in making the diagnosis were associated with the transfer of maternal antibodies to the fetus as well as with the fact that in many cases newborns do not have evident clinical symptoms of early congenital syphilis. In concordance with other groups, we believe that it is better to avoid overdiagnosing early congenital syphilis by providing specific treatment in doubtful cases, observing the dynamics of serological reactions and making no final diagnosis before the age of three months (1,2).
Women with syphilis are at risk for other infections including genital herpes, hepatitis С, hepatitis В, chlamydia, and tuberculosis, among others. It is evident that this risk is associated with social factors. Mothers with syphilis and their children should be examined thoroughly for other infections.

References

1. Borisenko КК, Loseva ОК, Dolya ОВ. РВС: Klinika, patomorfologia, diagnostika, lechenie, profilaktika. Russky Meditsinsky Zhurnal 1999, 09.02.
2. Shuvalova ТМ, Borisenko КК. K voprosu o klinike i diagnostike PVS. Infektsii peredaystciecya polovym pytem 1999, 4.
3. Shaparenko МV, Antonjev АА, Milich МV. Klinicheskie i serologicheskie osobennosti PVX v nastojachshee vremja. Vestnik dermatovenerologii 1990, 6.
4. Korotkin NG, Chininiva EG. Sovremennie osobennosti techeniya vrozhdennogu sifilisa. Pediatriya 1998, 3.
5. Zimmerman R., Informationnyi Bulleten ZPPP 1994, 3.
6. Flad JM, Vainshtok GS, Guroi МЕ. Obzornaya informatsiya IPPP 1999, 4.


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