AffiS RESEARCHVolume 2, Number 4, 1986Mary Ann Liebert, Inc., Publishers

SYPHILIS IN HTLV-III INFECTEDMALE HOMOSEXUALS

Jens Hein Sindrup, Kaare Weismann, and Gunhild Lange WantzinThe Department of Dermatology and Venereology, Bispebjerg Hospital, Copenhagen, Denmark

ABSTRACT

Out of 100 male homosexual persons screened for AIDS, 54 were found to be HTLV-III antibody positive. Of these, 34 (63%) had a positive history of syphilis,as compared to 16 (35%) of the 46 HTLV-III antibody negative persons (P<0.01).In the HTLV-III antibody positive group 12 (22%) had had more than three syphi¬lis infections as compared to none in the negative group (P=0.02).

The frequency of a previous primary, secondary, and latent syphiliticinfection was different in the two groups.

During the 1970s and early 1980s the incidence of syphilis in the U.S.A.and in Denmark was increasing, but from 1982 the incidence decreased markedly,possibly a consequence of the fear of AIDS, which appeared in 1981-82. It isspeculated that the high frequency of syphilis among homosexual men might havebeen a co-factor for the acquisition of the HTLV-III infection.

INTRODUCTION

It is well known that homosexual males constitute the majority of AIDSpatients in the U.S.A. and Europe. In the U.S.A. the percentage of homosexualsis about 73% (1) and in Denmark 92% (2). Homosexual men frequently have a

history of multiple sexually transmitted diseases (3). In the present study,we focused on the occurrence of syphilis in HTLV-III infected homosexuals.

MATERIALS AND METHODS

From October 1984 through April 1985, a total of 100 homosexual males witha mean age of 36 years residing in the Copenhagen area were screened for AIDSassociated abnormalities. Peripheral blood was investigated for antibodies(ab) of HTLV-III by ELISA and Western blot. In addition, blood samples wereexamined for T-lymphocyte subpopulations, T-helper/suppressor lymphocyte ratio,hemoglobin, leukocyte and thrombocyte counts, and syphilis serology.

Positive information about previous syphilis was confirmed by studying

285

records at the various clinics for venereal diseases in Copenhagen, and by helpof the central Wassermann file of the State Serum Institute in Copenhagen.

For statistical evaluation the X -test, Fisher's exact test, randomizationtest, and calculation of odds ratio and 95% confidence intervals were under¬taken. All tests were performed two-sided. A P-value below 0.05 was consid¬ered statistically significant.

RESULTS

Fifty-four of the 100 persons were HTLV-III ab positive and 46 were HTLV-III ab negative. Among the seropositive men 34 (63%) had a positive history ofsyphilis, as compared to 16 (35%) of the seronegative men (P<0.01). The oddsratio was estimated to be 3.2 (95% confidence limit for the true value 1.30-7.69).

Among the 50 patients with a positive history of syphilis, 34 (68%) were

found to be HTLV-III ab positive, compared to 16 (32%) of the seronegativegroup (P=0.01). The number of syphilis infections was significantly higher inthe HTLV-III ab positive group (P<0.01). HTLV-III ab positives had had an

average of 1.44 cases of syphilis per patient, the HTLV-III ab negatives 0.54.In the seropositive group 12 (22%) had had multiple (>3) syphilis infections(P=0.02).

The frequency of primary, secondary, and latent asymptomatic syphilis inthe two groups was found to differ significantly (P<0.01). In the HTLV-III abpositives 78 episodes of syphilis infections were noted (4 episodes unclassi¬fied), and in the HTLV-III ab negatives 25 episodes could be classified (2episodes unclassified). The frequency of the various clinical forms of syphi¬lis in both patient groups was significantly different from an equal distribu¬tion (P<0.05) (Fig. 1).

43°/.

P<Q05

HTLV-IDab POSITIVEGROUP (N=34)WITHSYPHIUS(n=74)

HTLV-mab NEGATIVEGR0UP(N=16)WITHSYPHILIS(n=23)

Fig. 1-

Primary (P), secondary (S), and latent (L) syphilis re¬

corded among HTLV-III antibody positive and negativehomosexuals.

DISCUSSION

We found an increased frequency of HTLV-III infection in homosexual men

who had a past history of syphilis. Others have failed to show such a relation

286

(4). Multiple syphilis infections were more frequently noted in HTLV-III abpositives, and more than 3 episodes of syphilis were found only in this group.The distribution of the various forms of syphilis in the two groups was differ¬ent. Thus, more than half of syphilis infections in the HTLV-III ab seronega¬tive group were chancres, as compared to only 20% in the seropositive group.This could be a consequence of missing rectal chancres in receptive homosexu¬als, but Christophersen et al. (5) in their study on a similar group of homo¬sexuals found no difference in the sexual performance of HTLV-III positive andnegative patients. Asymptomatic latent syphilis constituted 37% of the infec¬tions in the positive group as compared to 9% of the HTLV-III ab negativecases. This difference is unexplained but one could speculate that an alteredimmune response in HTLV-III infection played a role. Other studies have to bedone to evaluate this possibility.

The high incidence of HTLV-III infection among patients with a positivehistory of syphilis could be explained by an overall increased frequency ofsexually transmitted diseases in promiscuous homosexuals (3), but syphiliscould also theoretically be a co-factor for the acquisition of HTLV-III infec¬tion. The number of registered syphilis cases in Scandinavia and the U.S.A.increased during the 1970s and early 1980s up to a zenith in 1982, about one

year after the AIDS epidemic broke out (6). In the U.S.A., the incidence ofsyphilis peaked with an incidence of 22.5 primary and secondary cases per100,000 male inhabitants; in Denmark the figure was 19.3 per 100,000. Theincrease was mainly due to syphilis cases among homosexual men in urban areas,as reflected by an f/m sex ratio increasing from 1:2 to 1:3.2 in the U.S.A.during the 1970s. In Denmark the ratio went as high as 1:7 in 1980. After1982 the ratio was reduced as the incidence of syphilis declined. Thus, thereduction in syphilis was mainly due to fewer male cases. This is most likelyexplained as a consequence of the fear of acquisition of AIDS as a sexuallytransmitted disease (7). A high incidence of syphilis could have played a rolein the spread of HTLV-III infection. Sexual practices, especially anal inter¬course, are likely to produce injury of skin and mucous membranes and, in caseof preexisting lesions, exchange of secretions thus allowing penetration ofother infectious agents. Furthermore, syphilis is known to induce immunosup-pression (8), which theoretically might render the host more susceptible toother pathogens such as the HTLV-III virus. Further studies will have to beperformed to sustain this notion.

ACKNOWLEDGEMENTS

HTLV-III serology was performed by Bj arne 0rskov Lindhardt, M.D., theFibiger Institute, and by Jan Gerstoft, M.D., the State Serum Institute.

REFERENCES

1. CENTERS FOR DISEASE CONTROL (1985). Morbid. Mortal. Weekly Rep. 34, 245-248.

2. EPI-NYT (1985). Department of Epidemiology, the State Serum Institute,Copenhagen, No. 33/34.

3. FULFORD, K.W.M., CATTERAL, R.D., HOINVILLE, E., LIM, K.S., and WILSON,CD. (1983). Social and psychological factors in the distribution of STDin male clinic attenders. III. Sexual activity. Br. J. Vener. Dis. 59,386-393.

4. MAYER, K.H., AYOTTE, D., GR00PMAN, J.E., STODDARD, A.M., SARNGADHARAN, M.,and GALLO, R. (1986). Association of human T lymphotropic virus type IIIantibodies with sexual and other behaviors in a cohort of homosexual men

from Boston with and without generalized lymphadenopathy. Am. J. Med. 80,357-363.

287

CHRISTOPHERSEN, I., MENNE, T., ARENDRUP, M., et al. (1986). LAV/HTLV-IIIInfektion hos en gruppe homo- og biseksuelle maend i 1983 og 1985.Ugeskr. Laeg. 148, 863-865.

POULSEN, A., ULLMAN, S., and WEISMANN, K. (1986). Gonoré og syphilis iDanmark i perioden 1980-1984. Ugeskr. Laeg. 148, 992-993.

POULSEN, A. and ULLMAN, S. (1985). AIDS-induced decline of the incidenceof syphilis in Denmark. Acta Dermato-vener. (Stockholm) 65, 567-569.

J0RGENSEN, A.S., EL'RAMLEY, M.A.S., JENSEN, J.R., FROM, E., THESTRUP-andPEDERSEN, J. (1984). Immunosuppression in syphilis. Eur. J. Sex. Transm.Dis. 2, 5-9.

CENTERS FOR DISEASE CONTROL. Sexually Transmitted Disease StatisticalLetter. Calendar Years 1977-1983. Venereal Disease Control Division:Atlanta.

o

Statistisk Arbog 1977-1984. Danmarks Statistik: Copenhagen. (DanishStatistical Annuals 1977-1984.)

EPI-NYT. Department of Epidemiology, the State Serum Institute, Copenha¬gen. Week 1, 1984 and week 1, 1985.

Address reprint requests to:K. Weismann, M.D.

Department of Dermatology and VenereologyBispebjerg Hospital

DK-2400 Copenhagen NVDenmark

288