Testing for chlamydia antibodies in recurrent spontaneous abortion

LH activity from birth may have a sex reversed phenotype almost identical to the 46,XY sry⫺ Swyer syndrome. The clinical differences between the two (46,XY sry⫺ and 46,XY LHR⫺) are not striking except for three important features. The 46,XY LHR⫺ individual has a well-developed blind vaginal pouch and at the time of surgery mu¨llerian structures are not identifiable. Bilateral small testes are usually found, but they are frequently “hiding out” in the inquinal canal or may never be found. The operating surgeon needs to be prepared in advance for what may be a difficult search and eliminate mission. The testes, when found, are small and invariably devoid of Leydig cells. The latter being the reason for the rubric Leydig cell hypoplasia. It is important to keep all of this in mind because extirpating the adnexa in an individual with 46,XY sry⫺ sex reversal (Swyer syndrome) is easy, but finding the testes in a 46,XY LHR⫺ individual, who carries a null mutation in the LH receptor may be difficult even in experienced hands. Exploration of both inquinal canals is frequently necessary. At times it is difficult to know when to give up looking and resort to other indirect, but still not absolute, means of testicular identification (ultrasound with Doppler, MRI, hCG stimulation, etc.). On the other hand, an identical null LHR mutation in a 46,XX individual seems to give less pronounced phenotypic findings. The handful of clinically affected 46,XX LHR⫺ females ascertained as sisters of clinically affected males (46,XY,LHR⫺) have irregular menses and infertility (3). The phenotype is an inconsistent one and frequently lacks specificity when it occurs on the XX background. The LHR⫺ genetic females in the families, where an inactivating mutation in the LH receptor is segregating, require careful histories and endocrine studies. One must obtain a firmer grasp on the clinical and biochemical phenotype of these individuals. For example, “Did they ever have regular menses or pregnancies” prior to ascertainment? One of the best single case reports describing the clinical phenotype, including ovarian biopsy, was published by our correspondent Doctor Toledo and his colleagues in 1996 (4). It is perhaps stretching things a bit to categorize the 46,XX LHR⫺ females under the broad “rubric” of ovarian failure or gonadotropin resistant ovary, until more cases are carefully studied at the clinical and molecular level. In fact, some polycystic ovary syndrome (PCO) “watchers” might see this as the opportunity to find a continuum of LH mutations that can solve the eternal riddle of PCO. This could result in immediate unemployment for many of our colleagues, who have spent their careers “not finding the cause of PCO.” Overall, the unraveling story in man and mouse models (knockouts and knockins) seems to suggest that XY individuals need LH more than FSH and for XX individuals FSH is the more critical of the two tropic hormones. It is interesting that the receptors for these two peptides (FSHR and LHR) map close to each other on chromosome 2q. We owe considerable debt to the group from Saˆo Paulo, including Doc656

Letters to the Editor

tor Ana Latronico, Stavros Stavrou from Cornell, and also George Chrousos from NIH, who have spearheaded the efforts to study LH mutations (5). As Doctors Toledo and Marino preach to us, this is only the beginning. The DNAs of more patients from more pedigrees need to be studied, including more 46,XY LHR⫺ sex-reversed males with Leydig cell hypoplasia. More details are also needed concerning the downstream signaling system for LH in normal and pathologic situations. Deborah Segaloff at the University of Iowa is one of the most ardent investigators in this area (6). Perhaps LH mutations will be the “Lost Planet” for more than one clinical phenotype or just another dinosaur—take your pick. When the final answer comes, it may come from Saˆo Paulo. One way or the other all of this is forcing us to look at sexual differentiation in a different way. Several months ago I attended a splendid symposium on sexual differentiation at a meeting of the American Society of Human Genetics where Harry Ostrer (Clinical), Holly Ingraham (Sf-1), Andrew Sinclair (SRY), Jennifer Graves (evolutionary Y), and Seppo Vainio (Wnt-4) provided an exciting update on the topic. Conspicuously missing were mutations in the LH receptor. I want to thank our Brazilian colleagues for reminding us to keep a close eye on future developments in this area. Perhaps the lesson we can learn from them is that this syndrome may seem at first to be as “rare as hen’s teeth, but sometimes as every good biologist knows you can learn a lot from a hen with teeth.” References 1. Aittomaki K, Herva R, Stenman U-H, Juntunen K, Ylostalo P, Hovatta O, et al. Clinical features of primary ovarian failure caused by a point mutation in the follicle stimulating hormone receptor gene. J Clin Endocrinol Metab 1996;81:3722– 6. 2. Jones GS, de Moraes-Ruehsen M. A new syndrome of amenorrhea in association with hypergonadotropism and apparently normal ovarian follicular apparatus. Am J Obstet Gynecol 1969;104:597– 600. 3. Latronico AC, Segaloff DL. Naturally occurring mutations of the luteinizing-hormone receptor: lessons learned about reproductive physiology and G protein-coupled receptors. Am J Hum Genet 1999;65:949 –58. 4. Toledo SPA, Brunner HG, Kraaij R, Post M, Dahia PLM, Hayashida CY, et al. An inactivating mutation of the luteinizing hormone receptor causes amenorrhea in a 46,XX female. J Clin Endocrinol Metab 1996; 81:3850 – 4. 5. Latronico AC, Anasti J, Arnhold IJP, Rapaport R, Mendonca BB, Bloise W, et al. Brief report: testicular and ovarian resistance to luteinizing hormone caused by inactivating mutations of the luteinizing hormonereceptor gene. N Engl J Med 1996;334:507–12. 6. Chen S, Shi H, Liu X, Segaloff DL. Multiple elements and protein factors coordinate the basal and cyclic adenosine 3⬘,5⬘-monophosphateinduced transcription of the lutropin receptor gene in rat granulosa cells. Endocrinology 1999;140:2100 –9.

Paul G. McDonough, M.D., Editor, Letters PII S0015-0282(99)00581-6

Testing for Chlamydia Antibodies in Recurrent Spontaneous Abortion To the Editor: The article by Paukku et al. (1) on serum antibodies to Chlamydia trachomatis and recurrent pregnancy loss is, unVol. 73, No. 3, March 2000

fortunately, flawed and misleading. The first sentence in results states that “No statistically significant differences in the frequencies of IgG or IgA antibodies were observed between the recurrent pregnancy loss (RPL) and control groups.” However, by applying Fisher’s exact test to the data from the microimmunofluorescence (MIF) test in Table 1 it is clear that the women in control group A had a higher prevalence of IgG antibodies to C. trachomatis than did either of the two experimental groups (P⬍.001). Thus, one could interpret from their data that antichlamydial antibodies might protect against recurrent abortion. This is intuitively unlikely but one must accurately state and attempt to interpret the data. Table 1 also presents data using the recombinant ELISA (rELISA) test that differs considerably from the MIF results. However, the rELISA results and their difference from MIF is not mentioned at all in “Results” or “Discussion.” Again, if inconsistent data are presented, it must be explained, not ignored. The authors claim that serum IgA antibodies are indicative of an active infection. However, their observation of a higher prevalence of IgA antibodies to C. trachomatis in the control group argues against this. In the next to last paragraph of the “Discussion,” it appears that the authors are suggesting that the control women with antichlamydial IgA have an active chlamydial infection. Surely, a more likely interpretation is that the IgA is not indicative of active infection. A previous study by the same authors (2) and numerous other studies have shown that serum IgA antibodies are not a good marker of a current chlamydial infection. Finally, the authors conclude that “women with RPL do not benefit from screening for chlamydial IgG or IgA antibodies.” Assuming that their analyses and interpretations are correct, can the results of testing a small number of Scandinavian women be universally applied? The terrific job of the Scandinavian countries in recent years in greatly reducing the rate of chlamydial infections is well known. One would not expect to see much Chlamydia-associated pathology in this population. However, what testing might or might not be necessary in Finland is of questionable relevance to regions with high rates of C. trachomatis infections. My own bias is that testing for cervical antibodies to C. trachomatis is more relevant than testing for serum antibodies and testing for antibodies to the chlamydial 60-kd heat shock protein is even more specific for current infection. However, whatever testing may be available at a particular location, I believe it is still prudent, at least in the United States, to rule out the presence of a C. trachomatis infection in women with recurrent spontaneous abortion. Steven S. Witkin, Ph.D. Division of Immunology and Infectious Diseases Department of Obstetrics and Gynecology Weill Medical College of Cornell University New York, New York September 30, 1999

FERTILITY & STERILITY威

References 1. Paukku M, Tulppala M, Puolakkainen M, Antilla T, Paavonen J. Lack of association between serum antibodies to Chlamydia trachomatis and a history of recurrent pregnancy loss. Fertil Steril 1999;72:427–30. 2. Mattila A, Miettinen A, Heinonen PK, Teisala K, Punnonen R, Paavonen J. Detection of serum antibodies to Chlamydia trachomatis in patients with chlamydial and nonchlamydial pelvic inflammatory disease by the IPAzyme chlamydia and enzyme immunoassay. J Clin Microbiol 1993; 31:998 –1000.

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Reply of the Author: We thank Dr. Witkin for his interesting comments regarding our paper of Chlamydia trachomatis and recurrent pregnancy loss (RPL) (1). As correctly pointed out by Dr. Witkin, results by recombinant ELISA (rELISA) differ noticably from those by microimmunofluorescence (MIF). These two tests were chosen to be used, because they represent two independent serologic methods; MIF detects antibodies to C. trachomatis-specific major outer membrane protein, whereas rELISA detects antibodies to chlamydial lipopolysaccharide, thus identifying antibodies to C. pneumoniae and C. psittaci as well. We agree with Dr. Witkin that the presence of IgA antibodies is not a perfect marker of an active chlamydial infection. However, compared with IgG antibodies, which can persist up to several years after eradication of the infection (2), the shorter half-life of IgA antibodies allows them, at least theoretically, to serve as a better sign of a current infection (3, 4). Spontaneous abortion is an emotionally devastating event. Accompanying the often encountered lack of an identified cause for a previous pregnancy loss is the anxiety surrounding the next conception. This situation tends to lead to extensive investigations for possible causes. The objective of our study was to evaluate whether women with RPL do benefit from testing for antichlamydial antibodies. As shown by our results, the presence of either IgG or IgA antibodies has no correlation to the occurrence of RPL. Therefore, it is unnecessary to increase the burden of tests for women with RPL by serologic screening for antichlamydial antibodies. Maarit Paukku, M.D., Ph.D. Department of Virology University of Helsinki Helsinki, Finland October 22, 1999

References 1. Paukku M, Tulppala M, Puolakkainen M, Anttila T, Paavonen J. Lack of association between serum antibodies to Chlamydia trachomatis and a history of recurrent pregnancy loss. Fertil Steril 1999;72:427–30. 2. Puolakkainen M, Vesterinen E, Purola E, Saikku P, Paavonen J. Persistence of chlamydial antibodies after pelvic inflammatory disease. J Clin Microbiol 1986;23:924 – 8. 3. Tomasi TB, Grey HM. Structure and function of immunoglobulin A. Prog Allergy 1972;16:81–113. 4. Miettinen A, Heinonen PK, Teisala K, Punnonen R, Paavonen J. Antigen specific serum antibody response to Chlamydia trachomatis in patients with acute pelvic inflammatory disease. J Clin Pathol 1990;43:758 – 61.

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