bubble_chart Overview

Congenital syphilis, also known as congenital syphilis, is a syphilis spirochete disease acquired by the fetus from the mother. Pregnant women with syphilis can transmit the syphilis spirochete to the fetus through the placenta as early as 6 weeks of pregnancy, leading to congenital syphilis. Among the affected fetuses, 30% result in dead fetus, stillbirth, or late abortion. Cases occurring within 2 years of age are classified as early congenital syphilis, while those occurring after 2 years are classified as advanced stage congenital syphilis. Early lesions are more severe than acquired syphilis but do not present with hard chancre. Advanced stage cases are milder, with less involvement of the heart and blood vessels but more frequent involvement of bones, eyes, ears, and nose.

bubble_chart Diagnosis

(1) Medical History The mother has syphilis and may have a history of late abortion, stillbirth, or premature labor. The placenta is enlarged and pale. (2) Clinical Symptoms

1. In severe cases of early congenital syphilis, premature labor may occur. Symptoms generally appear 3 weeks after birth. (1) Poor development and nutrition, loose skin resembling an elderly appearance. If hypoalbuminemia is present, generalized edema may occur. (2) Skin and mucous membrane lesions commonly include maculopapular rashes, peeling of palms and soles, alopecia areata, and paronychia. Radial fissures and scars may appear at the corners of the mouth, around the anus, and in the perineal area. (3) Syphilitic rhinitis: Seropurulent or bloody discharge, stuffy nose, difficulty breathing and suckling. Severe cases may damage the nasal bones, leading to a sunken nasal bridge (saddle nose). (4) Bone lesions manifest as osteochondritis and periostitis, causing limb pain, immobility, and syphilitic pseudoparalysis. (5) Generalized lymphadenopathy, hepatosplenomegaly, and sometimes persistent jaundice.
2. Advanced-stage congenital syphilis: (1) Skin and mucous membrane lesions: Nodular syphilides and gummas may occur, with perforation of the hard palate and nasal septum, and saddle nose. (2) Bones: Thickening of the middle tibia with anterior protrusion (saber shin), syphilitic arthritis causing knee joint swelling, effusion, or stiffness. (3) Hutchinson’s triad: Hutchinson’s teeth (narrow incisors with a crescent-shaped notch at the lower edge), interstitial keratitis, and nerve deafness. (4) Neurological damage may occur in children aged 1–10 years, presenting as hemiplegia, stiffness, intellectual disability, epilepsy, etc. 3. Congenital latent syphilis: No clinical symptoms, but syphilis serology is positive. (3) Laboratory Tests 1

. Syphilis spirochete examination: (1) Dark-field microscopy: Scrapings from skin lesions or lymph node aspirates are directly smeared and examined under a dark-field microscope to observe motile syphilis spirochetes. (2) Immunofluorescence staining: Green-stained syphilis spirochetes can be seen under a fluorescence microscope. 2. Syphilis serological tests: (1) Non-treponemal antigen serological tests: These tests are highly sensitive but less specific and prone to false positives. They are generally used for screening and quantitative testing to monitor treatment efficacy, relapse, and reinfection. Examples include the Venereal Disease Research Laboratory (VDRL) test, Rapid Plasma Reagin (RPR) test, and Unheated Serum Reagin (USR) test. These three tests are simple to perform, but the VDRL requires microscopic reading and has low sensitivity for initial-stage syphilis. The latter two are modifications of the VDRL antigen, with RPR being readable by the naked eye and simpler to perform. (2) Treponemal antigen serological tests: These use syphilis spirochetes as antigens to detect specific antibodies in serum. They are highly specific and sensitive and are generally used as confirmatory tests. However, the antibodies detected remain positive even after adequate treatment, so these tests cannot monitor treatment efficacy, relapse, or reinfection. Examples include the Fluorescent Treponemal Antibody Absorption (FTA-ABS) test and the Treponema pallidum Hemagglutination Assay (TPHA). 3. The Wassermann complement fixation test and Kahn precipitation test have largely been replaced by the newer methods mentioned above, though they are still used in some remote areas. 4. Cerebrospinal fluid (CSF) examination: In patients with syphilitic meningitis, CSF white blood cell counts may reach up to 500×10^6/L, with elevated globulin levels, positive VDRL test, and positive colloidal gold test. 5. X-ray examination: Thickening of long bone periosteum, osteoporosis, and possible destruction of the metaphysis.

bubble_chart Treatment Measures

﹝Treatment﹞

(1) Penicillin is the first choice. Procaine penicillin G, 50,000 U/(kg·d), intramuscular injection, for 10-14 days. Benzathine penicillin, 50,000 U/kg, single intramuscular injection, not used for neurosyphilis. To prevent the Jarisch-Herxheimer reaction, the initial dose should be small, 30,000-50,000 U per dose.

(2) For patients allergic to penicillin, other antibiotics such as erythromycin can be used, with a daily dose of 20-30 mg/kg for 10-14 days. Other new macrolides such as azithromycin and roxithromycin can also be used. For children over 8 years old, tetracycline can also be used.

bubble_chart Prevention

(1) Early diagnosis and thorough treatment.

(2) Prenatal care: Conduct serological tests for suspected cases as early as possible, aiming for thorough treatment before pregnancy: weeks to avoid fetal infection. Even if penicillin treatment is administered in the late stage of pregnancy [third trimester], it can reduce the incidence of congenital syphilis.

bubble_chart Differentiation

Skin lesions should be differentiated from pemphigus, scabies, drug rash, etc. Syphilitic rhinitis should be distinguished from nasal diphtheria, and pseudoparalysis should be differentiated from scurvy, rickets, and subcutaneous bone nodules.