Correlation of colposcopic anogenital findings and overall assessment of child sexual abuse: prospective study

PCH Cheung, CH Ko, HYM Lee, LMC Ho, WWK To, PLS Ip
Department of Paediatrics and Adolescent Medicine, United Christian Hospital, 130 Hip Wo Street, Kwun Tong, Hong Kong

OBJECTIVE. To examine the relationship between colposcopic anogenital findings and overall assessment of sexual abuse.

DESIGN. Prospective study.

SETTING. Regional hospital, Hong Kong.

PATIENTS. Seventy-seven children (mean age, 6.5 years; range, 6 months-16 years) referred consecutively for sexual abuse evaluation between July 1999 and June 2002 were included.

MAIN OUTCOME MEASURES. Colposcopic anogenital findings (categorised as normal, non-specific, concerning for abuse, or clearly abnormal) were correlated with the overall assessment of likelihood of abuse (classified as no evidence of abuse, possible abuse, probable abuse, or definite abuse). The sensitivity and specificity of clearly abnormal findings in detecting definite abuse were computed, and the diagnostic impact of colposcopy findings were expressed as likelihood ratios.

RESULTS. Anogenital findings were normal in 45% of patients, non-specific in 29%, concerning for abuse in 13%, and clearly abnormal in 13%. Seven of the 16 confirmed cases of sexual abuse had normal or non-specific findings. Overall assessment showed that 46% of all patients had no evidence of abuse, 20% had cases of possible abuse, 13% had cases of probable abuse, and 21% had cases of definite abuse. The sensitivity and specificity of abnormal anogenital findings in detecting definite abuse were 56.3% and 98.4%, respectively. Colposcopy showed a fair correlation with the overall assessment of abuse (weighted kappa, 0.245). The diagnostic impact of normal, non-specific, concerning, and clearly abnormal findings in terms of likelihood ratios were 0.23, 1.12, 0.00, and 34.30, respectively.

CONCLUSIONS. Anogenital findings are often normal or non-specific in sexual abuse. In general, colposcopy examination findings do not directly reflect the final diagnosis. A category-4 finding on colposcopy is very helpful in confirming definite abuse, whereas other findings do not rule out the diagnosis.

Hong Kong Med J 2004;10:378-83

Key words: Anus/injuries; Child abuse, sexual; Genitalia, female; Colposcopy