Volume 5 Issue 1                                                                           January 2001

LABORATORY TESTING IN CHILDREN WITH SUSPECTED SEXUAL ABUSE

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Laboratory testing in children with suspected sexual abuse has two goals: medical treatment of infectious diseases and forensic documentation.  Forensic studies should be performed when the examination is within 72 hours of acute sexual contact or there is evidence of acute injury.  In addition to testing for STDs, biological trace evidence (epithelial cells, semen, blood) should be sought.  Chain of evidence should be maintained for legal documentation.  If there is external bruising, consider PT, PTT, BLEEDING TIME and CBC with platelet count.  Universal screening of sexually abused children of STDs has had a yield of 5%.  Some experts believe that STD testing should be reserved for high risk cases: suspected perpetrator with a high risk for STD, multiple perpetrators, evidence of genital, oral or anal penetration, family preference, postpubertal patients, symptomatic patients, community with high prevalence of STDs, STDs in household.  Testing for STDs needs to consider incubation time and mode of contact (oral, anal, genital).  Establishing a negative status becomes important if conversion to positive status is to be meaningful.  In menarchal females, a pregnancy test is absolutely required.  A Pap smear as well as a wet mount for bacterial vaginosis should be performed for these patients. Vulvovaginitis, usually not an STD, can be cause by H. flu and Strep pneumonia.

Disease	Epidemiology	Screening Lab	Follow-up Considerations
Chlamydia Trachomatis^1	Most common STD Incubation variable Usually <1 week Infections at birth can persist for up to 3 years.	PCR or LCR most sensitive Culture required for forensic evidence Consider rectal as well as vaginal/penile specimens	If acute exposure May repeat in one month
Neiserria Gonorrhea^1	Incubation period 1-10 days Usually <4 days	PCR or LCR most sensitive Culture required for forensic evidence Consider oral & rectal as well as vaginal/penile specimens Positive isolates should be confirmed by two independent testing principles	If acute exposure Repeat in 2 weeks
Syphilis^1	Incubation 10-90 days	RPR or VDRL	Repeat at 6 weeks to 90 days FTA-ABS/MHA-TP if positive
HIV^2	Penile/vaginal risk <2/1000 Anal intercourse risk ~2/100	Serology	Most infections will elicit antibodies in 3-6 months but can be longer PCR can be considered
Hepatitis B	~30 days incubation	Hep B surface Ab (vaccine) Hep B Core Ab Hep B Surface Antigen	Consider vaccination status
Hepatitis C	Extended incubation	Hep C Antibody	PCR available
Trichomonas^3	Incubation 4-28 days	Wet mount and culture
Herpes 1 & 2	Incubation 1-26 days	Ig M for primary infection Culture
Human  Papilloma Virus	Unknown dormancy	Biopsy	Controversial significance
Pediculosis Capitis		Identification with hand lens

¹ Diagnostic of sexual abuse if not perinatally acquired

² Diagnostic of sexual abuse if not perinatally or transfusion acquired

³ Highly suspicious of sexual abuse

References:  MMWR 1998, 47:111-116

                     Pediatric Red Book 2000, 138-147

                     Pediatrics 1999, 103: 186-191, See Erratum page 1049