871 RHEUMATOID ARTHRITIS AND ORAL CONTRACEPTIVES

SiR,—The findings of Sally Wingrave and Dr Kay (March 18, p. 569) suggest that oral-contraceptive use may lower the incidence of rheumatoid arthritis (R.A.). If oral contraceptives have such an effect then we would expect to see a reduction in the incidence of R.A. in women in the past few years. Few studies of R.A. incidence have been done, and none per-

mits an examination of secular trend. However, under the auspices of the Rochester Epidemiological Program Project,’ we are just completing a 25-year study of the incidence of R.A. in the population of Rochester, Minnesota, which offers some support to the thesis proposed by Wingrave and Kay. DEFINITE R.A. IN

ROCHESTER, MINNESOTA, 1950-74

*Cases per 100 000 persons per year age White population.

adjusted

to

1960 U.S. total

All cases of probable and definite R.A. (A.R.A. criteria) diagnosed for the first time in Rochester residents during the period 1950-74 have been identified. The table shows the ageadjusted (1960 U.S. White) incidence-rates of definite R.A. by 5-year calendar intervals for each sex. Whereas rates for both males and females rose during the first 15 years of the study, the male rates levelled off while the female rates fell sharply after 1965. This decline fits the pattern to be expected if development of R.A. is affected by oral-contraceptive use. In an effort to explain the decline in incidence among females we reviewed the medical records of patients diagnosed as having many other related disorders and discussed the problem with the rheumatologists at the Mayo Clinic. However, we found no additional cases of R.A. and unearthed no diagnostic changes in the past 10 years which could explain a differential loss of female over male cases. Nevertheless, we cannot be certain that some confounding factor is not at work. To determine the pattern of use of oral contraceptives in the community and among our R.A. patients a case-control study will be required. However, the data we have are consistent with the hypothesis that oral contraceptives might protect some segment of the female population from R.A. A. LINOS

J. W. WORTHINGTON Mayo Clinic, Rochester, Minnesota 55901, U.S.A.

W. M. O’FALLON L. T. KURLAND

IS GLOMERULONEPHIRITIS AFTER BACTERIAL SEPSIS ALWAYS BENIGN?

SIR,-Glomerulonephritis secondary to indolent bacterial endocarditis or infection of a ventricular-vascular shunt is considered to be a self-limiting process, once the focus of infection is eliminated °3 The nephritis results from a circulating immune complex of antibody with bacterial antigen which lodges in the glomerulus and fixes complement;4 once the organism is 1. Kurland, L. T., Elveback, L. R., Nobrega, F. T. Proceedings of the sixth international scientific meeting on the Uses of Epidemiology in Planning Health Services. International Epidemiological Association, Belgrade, 1973. 2. McDonald, B. M., McEnery, P. T. Pediat. Clins. N. Am. 1976, 23, 691. 3. Dobrin, R. S., Day, N. K., Quie, P. G., Moore, H. L., Vernier, R. L., Michael, A. F., Fish, A. J. Am. J. Med. 1975, 59, 660. 4. Strife, C. F., McDonald, B. M., Ruley, E. J., McAdams, A. J., West, C. D. J. Pediat. 1976, 88, 403.

eradicated, immune-complex formation is

soon

terminated,

activation ceases, and acute glomerular inflammation subsides. Healing is thought to be complete except in rare instances, and residual renal damage has seldom been

complement

reported.s We have seen two children--one with a ventricular-jugular shunt for hydrocephalus and the other with surgically corrected tetralogy of Fallot-who seem to be exceptions to the above sequence. Both had normal renal function (normal urinalysis and blood-urea or creatinine) before their acute presentation with fever, leukocytosis, hypocomplementaemia, hsematuria, proteinuria, azotaemia, and hypertension. Blood cultures were positive. Both children were treated with intravenous antibiotics for at least 6 weeks. In the child with hydrocephalus the shunt was replaced 72 h after treatment began. Blood cultures became sterile in 3 days, temperature and whiteblood-cell counts became normal in 4 days, and the children felt better within 9 days. Percutaneous renal biopsy in the second week in the child with congenital heart-disease revealed

type-i membranoproliferative glomerulonephritis. Despite sterile blood cultures and normal C3 levels, haematuria, proteinuria, and raised blood-urea associated with low serum levels of C4 and properdin persisted in both patients for 6 months. Subsequently, C4 and properdin also returned to normal, and the azotaemia and haematuria disappeared. 2 years later, however, both children had evidence of residual renal damage, as illustrated by hypertension and persistent proteinuria of at least 1 g/24 h. Three additional patients with ventricular-jugular shunts have also been observed who, although not studied during their acute disease, now have evidence of residual renal disease after an episode of "shunt glomeru-

lonephritis" more than 5 years ago. This experience suggests that immune-complex glomeru-

lonephritis secondary

to

bacterial endocarditis

or an

infected

ventricular-jugular shunt is not always benign. The renal lesion will usually heal completely but the final outcome is neither completely predictable nor uniformly favourable. In these two patients we precluded the formation of new immune complexes by eliminating the infecting organism (and, in one patient, the nidus of infection by removing the shunt, yet C4 and properdin levels remained low and hmmaturia continued for 6 months. We are not sure why this happened . The fact that haematuria disappeared when the complement titres returned to normal suggests that glomerular-bound immune complexes persisted and were responsible for continued complement fixation and persistent inflammation. However, synthesis of these two proteins may have been depressed after long-standing complement activation, as happens in hereditary angioneurotic oedema and systemic lupus erythematosus. In either case, persistently low serum levels of C4 and properdin in patients such as these may reflect chronic immune-complex disease and this could be useful in predicting the development of residual renal disease. Department of Pediatrics, Upstate Medical Center, Syracuse, N.Y. 13210, U.S.A.

ROGER E. SPITZER ANN E. STITZEL JOAN R. URMSON

URINARY ASCITES AFTER GYNÆCOLOGICAL LAPAROSCOPY

SiR,-Ureteroperitoneal fistula associated with urinary ascites is a rare complication of pelvic surgery.’ We have seen such a complication after gynaecological laparoscopy. A 27-year-old woman was admitted with ascites 3 weeks after laparoscopy done for investigation of secondary sterility. Wegmann, W., Leumann, E. P. Virchows Arch. 1973, 359, 185. 1. Bourdeau, G. V., Jindall, S. L., Gillies, R. R., Berry, J. V. Urology, 1974, 4, 209.

5.

Rheumatoid arthritis and oral contraceptives.

871 RHEUMATOID ARTHRITIS AND ORAL CONTRACEPTIVES SiR,—The findings of Sally Wingrave and Dr Kay (March 18, p. 569) suggest that oral-contracept...
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