David L. Ingram

A high degree of natural immunologic priming to the capsular polysaccharide may not prevent Haemophilus influenzae type b meningitis.

Background. A current debate is whether the immunologic priming of infants with Haemophilus influenzae type b (Hib) conjugate vaccines would be protective in the absence of circulating antibody to the capsular polysaccharide (PS). Data from the prevaccine era on the PS antibody responses of older children to Hib meningitis may be informative on this issue. Methods. PS antibody was assayed by radioantigen binding in sera taken in the first month postadmission in 47 children ages 2 to 136 months with culture‐proved Hib meningitis. Results. Sera obtained on admission had very low antibody concentrations, and the subsequent response during convalescence was age‐dependent. The major finding is that some patients, including 10 of 11 children older than 2 years, had substantial antibody elevations within a few days of admission, increases resembling the response to PS vaccine in infants primed with PS‐protein conjugate vaccines. Conclusions. In this group of patients with Hib meningitis, natural priming did not prevent infection. Hib may have the ability to invade despite the capacity for a vigorous antibody response.

Childhood vaginal infections: association of Chlamydia trachomatis with sexual contact

To determine whether infections with Chlamydia trachomatis in children were significantly associated with previous sexual contact, we studied 124 female children ages 1 through 12 years with previous sexual contact and 90 female children without previous sexual contact. Vaginal, pharyngeal and rectal cultures for C. trachomatis were performed. Ten children with previous sexual contact and none without previous sexual contact had vaginal infections (P = 0.022, chi square test with 2 degrees of freedom). Rectal infections (three) and pharyngeal infections (two) were too few to relate statistically to sexual contact. We recommend that all female children being evaluated for sexual abuse be cultured for C. trachomatis, inasmuch as vaginal C. trachomatis is an excellent marker of sexual contact.

Vaginal Chlamydia trachomatis infection in children with sexual contact.

To determine whether vaginal infections with Chlamydia trachomatis in children were associated with sexual contact, 50 children ages 1 to 12 years with a history of sexual contact and 34 children without such a history were studied. Vaginal, throat and rectal cultures for C. trachomatis and Neisseria gonorrhoeae were performed in all children. Three children with sexual contact and none of the children without a history of sexual contact had vaginal infections. The three infected children were asymptomatic and only one had had vaginal intercourse. None of the 10 children with a history of sexual contact and gonorrheal vaginitis had C. trachomatis isolated. Although C. trachomatis vaginal infections as detected by vaginal cultures are infrequent, we recommend that all girls being evaluated for sexual contact be routinely cultured for C. trachomatis so that those infected can be treated.

A Comparison of Sexually Transmitted Diseases (STDs) Found In A Total Of 696 Boys And 2973 Girls Evaluated For Sexual Abuse † 521

A Comparison of Sexually Transmitted Diseases (STDs) Found In A Total Of 696 Boys And 2973 Girls Evaluated For Sexual Abuse † 521

782 TIME OF DETECTION OF GROUP B STREPTOCOCCAL (GBS) CAPSULAR POLYSACCHARIDE (CPS) IN BODY FLUIDS IN THE COURSE OF EARLY ONSET GBS DISEASE

CPS can be detected in the body fluids of most newborns with GBS disease. To determine if CPS can be detected early enough (≤ 12 hours) in the course of GBS disease to assist in chosing therapy, randomly collected sera, urine and/or cerebrospinal fluid (CSF) from 13 neonates were tested for CPS by counterimmunoelectrophoresis. Of 10 with pneumonia and sepsis (2 also with meningitis) CPS was detected in serum, urine and/or CSF in 9 by 36 hours of illness. However, CPS was detected in sera in only 3 of 7 neonates during the first 12 hours of illness. CPS was detectable in urine of 2 of 2 neonates tested in the first 12 hours of illness when only 1 had detectable CPS in serum. CPS was also present in the urine of 3 of 3 other patients with CPS in their sera after 12 hours of onset of illness. Of 5 neonates with meningitis (2 also with pneumonia included above), CPS was detectable in the CSF at onset of illness in 3 of 4 with available CSF and not in the serum samples of 1 without available CSF. These data suggest that serum is not the ideal body fluid to test for the early detection of CPS in neonates with GBS disease, and that urine and CSF when appropriate may be better. It is recommended that several body fluids be tested during the course of the illness if antigen detection is to be used optimally as an aid in selecting therapy.

MODERATE SENSITIVITY, HIGH SPECIFICITY, AND LOW POSITIVE PREDICTIVE VALUE OF THE GROUP B STREPTOCOCCAL (GBS) LATEX AGGLUTINATION (LA) ANTIGEN DETECTION TEST

The purpose of this study was to evaluate the GBS LA test prospectively over 3.5 years in a hospital laboratory. Between 4/1/80 and 11/30/83, 869 urine samples and 302 cerebrospinal fluid (CSF) samples from 1035 patients evaluated for GBS sepsis and/or meningitis were tested by GBS LA. All patients had a blood culture and 302 also had a CSF culture for suspected meningitis. Seventeen patients had culture positive GBS sepsis or meningitis. Thirty-one patients had a positive GBS LA test for GBS antigen. Of these 31, 12 had GBS sepsis and/or meningitis by culture, 13 had GBS surface or gastrointestinal colonization but sterile blood ± CSF cultures, and 6 had no evidence of GBS colonization or infection.The test had a sensitivity=A/A+C=12/17=71%, specificity= D/B+D=999/1018=98%, and a predictive value of A/A+B=12/31=39%Conclusion: The low positive predictive value for the GBS LA test made an individual positive test difficult to interpret.

COUNTERIMMUNELECTROPHORESIS IN HEMOPHILUS INFLUENZAE TYPE B EPIGLOTTITIS AND PERICARDITIS

Counterimmunelectrophoresis (CIE) was used to detect polyribophosphate (PRP), the capsular polysaccharide antigen of Hemophilus influenzae type b (H.flu.b), in sera of patients with H.flu.b epiglottitis and sera and pericardial fluids of patients with H.flu.b pericarditis.CIE was performed for 30 mins. at 30 milliamps using (NH4)2 SO4 precipitated rabbit antisera and Hyland agar gel plates. The sera of 7 patients with H.flu.b epiglottitis were tested prior to IV Ampicillin therapy. Immunoprecipitin bands became visible in 3 specimens after cooling for 30 mins. and in a fourth after cooling for 10 hrs. Three sera contained 5 ng of PRP per ml, while the fourth contained between 2.5 and 5 ng of PRP per ml, a quantity which represents the lower limits of sensitivity for this technique. The brief course of epiglottitis prior to therapy may explain the small amount of PRP produced.In contrast, pericardial fluids and sera of 3 patients with H.flu.b pericarditis were markedly positive. Two pericardial fluids were quantitated. The first contained 5.85×105ng of PRP per ml and the second contained 19×105 ng of PRP per ml. The pericardial sac may function as a depot for large amounts of antigen.