Endometrial involution

1360 Correspondence

the mother had positive results only for the dye test (15 IU/ml), whereas the infant's serologic assays remained negative for anti-Toxoplasma IgG and IgM. Also in the woman we observed, it is not possible to confirm the recent toxoplasmic infection on the basis of the serologic follow-up, but unlike Konishi, we could identify a "limited" period of positivity for IgM against Toxoplasma that covers at least the first 18 weeks of pregnancy. In our case the positivity for anti-Toxoplasma IgM might be a result of natural antibodies induced by nontoxoplasmic antigens of placental origin or by other unidentified stimuli. It is known that toxoplasmic membrane antigens may cross-react with natural antibodies in patients who have never been infected with Toxoplasma, I. 2 but it is significant to note that natural antibodies may also influence highly specific serologic tests (ELISA for IgM and the dye test) for toxoplasmosIs. Because an acute toxoplasmic infection cannot be confirmed in the absence of increasing IgG titers in subjects suspected of recent infection, the dynamic study of humoral response to Toxoplasma gondii must be carefully evaluated, especially during pregnancy when a certain and early diagnosis is required. We thank Professor G. Desmonts for the authoritative supervision of this case. Nadia Gussetti, MD Ruggiero D'Elia, MD Department of Pediatrics University of Padova Via Giustiniani 3 Padova, Italy 35128 Attilio Mottola, MD Egidio Rigoli, MD Institute of Microbiology S. Maria dei Battuti Hospital Ca'Foncello Treviso, Italy 31100 REFERENCES 1. Desmonts G, Baufine-Ducrocq H, Couzinequ P, Peloux Y. Nouv Presse Med 1974;3:1547-9. 2. Potasman I, Araujo FG, Remington jS. j Clin Microbiol 1986;24:1050-4.

Reply To the Editors: I appreciate the interest of Dr. Gussetti and her colleagues in my work. They provided another case of a pregnant woman with high levels of naturally occurring immunoglobulin M (lgM) antibodies against Toxoplasma gondii. Serologic tests indicated positive results for IgM antibodies from 6 through 18 weeks' gestation, but IgG antibodies were consistently negative throughout the study period. Their report clearly shows that we cannot diagnose recent Toxoplasma infection from only the data of IgM antibodies. The detailed study of humoral immune responses to an acquired infection with this par-

May 1990 Am J Obstet Gynecol

asite, especially in symptom-free cases, will be needed for serodiagnosis of Toxoplasma infection during pregnancy. Our recent surveys of natural IgM antibodies among Japanese populations revealed that a small but significant number of people had such high levels of IgM antibodies to Toxoplasma gondii without a subsequent increase in IgG antibody level (rheumatoid factor and antinuclear antibodies were also negative). When paired sera collected at a I-year interval were tested for IgM antibodies, changes ~0.1 in enzyme-linked immunosorbent assay value was observed only in about 13% of the population, and no pairs showed changes ~0.2. Another serum population obtained over 4 years at yearly intervals also showed almost constant natural IgM antibody levels without any considerable changes. Moreover, similar frequency distribution patterns of IgM antibody levels were obtained in populations of pregnant and general women. In this sense, the reported case by Dr. Gussetti et al. in which positive IgM antibody levels were observed during the limited period may be rare and significant. Eiji Konishi, PhD Department of Medical Zoology Kobe University School of Medicine Kobe 650, Japan Endometrial involution To the Editors: We were particularly interested III the article of Check et al. (Check JH, Shanis BS, Stanley C, Chase JS, Nazari A, Wu CH. Amenorrhea in an ovulatory woman despite a normal uterine cavity: Case report. AMJ OBSTET GYNECOL 1989;160:598-9). We reported a similar observation in 1966 in a study on the menstrual endometrium. 1 The woman was 27 years old and, although she had secondary amenorrhea when she was first seen, she had four normal pregnancies. We believe that such cases favor an endometrial involution without associated tissue shedding. We think, in fact, that during normal menstruation the endometrium essentially undergoes a process of regression with reorganization and that tissue shedding is minimal or inconstant. 2 J. Ritter, MD Service de Gynecologie-Obstetrique I CHRU Strasbourg-Hopital de Hautepierre Avenue Moli'agere 67098 Strasbourg Cedex, France E. Philippe, MD Institut d'Anatomie Pathologique CHRU Strasbourg-BP 22 1 Place de I'Hopital 67064 Strasbourg Cedex, France REFERENCES 1. Philippe E, Ritter j, Gandar R. L'endometre biphasique normal en periode menstruelle. Gynecol Obstet (Paris) 1966;65:515-31. 2. Ritter j, Philippe E. La menstruation normale. Encyclo-

Correspondence

Volume 162 !';umber 5

paedia Medicine Chirurgie vol 10. Paris: Gynecologie, 1982:155.

Reply To the Editors: We thank Professeurs Ritter and Philipe for their letter. We obtained a computer search going back 30 years, but I'm afraid we did not adequately search the French literature. We are comforted that similar cases have been reported previously, and because of the suspicion of this possible preexistence, we did not make any claims that this was the first case report of this phenomenon. In fact, we did have a previous case of primary amenorrhea with apparent regular ovulation in which the patient conceived and then spontaneously aborted. Unfortunately, she never returned for more investigative procedures so we never submitted a case report. Jerome H. Check, MD Suite 1020 1015 Chestnut St. Philadelphia, PA 19107

HBsAg in placentas To the Editors: I read with great interest the article by Lucifora et al. (Lucifora G, Calabro S, Carroccio G, Brigandi A. Immunocytochemical HBsAg evidence in placentas of asymptomatic carrier mothers. AM J OBSTET GYNECOL 1988; 159:839-42). On review of the literature, this was the first description that HBsAg was detected in the placentas of HBsAg-positive asymptomatic carrier mothers. However, there were two mistakes in the manuscript. The first was in the right column of page 840, lines 4 to 7 from the top; the correct sentence should be "Positive controls were obtained by submitting to the same procedure sections obtained by biopsy of chronic active hepatitis B patients or acute exacerbation of hepatitis in HBsAg carriers. "1 The second mistake was in the left column of page 842, lines 18 to 19 from the top; the correct sentence should be "Babies born to HBsAg carrier mothers did not always have IgM anti-HBc."2 Moreover, we have pointed out that the cases infected in utero by hepatitis B virus (HBV) were most likely caused by transplacental leakage of HBeAg-positive maternal blood during pregnancy, which was clinically expressed by uterine contractions. This resulted in disruption of part of the placental barriers to let maternal blood leak into fetal circulation, such as in threatened abortion or threatened preterm labor. Moreover, the duration between the occurrence of the episode and delivery must be >6 weeks. Therefore, I point out the following: 1. The three carrier mothers must not be selected at random because the rate of HBV intrauterine infection is about 3% to 5% of perinatal transmission. 2. The three carrier mothers should not only be

1361

HBsAg-positive, but also HBeAg- and HBV-DNApositive, because the high infectivity of the carrier mother is the sole condition to possibly allow HBV intrauterine infection to occur. 3. The duration between the delivery and occurrence of threatened preterm labor in each case must be >6 weeks, which may be enough incubation time to let infection occur. 4. The three newborns should become HBV carriers because the placentas were infected by HBV with the evidence of HBsAg in them. H o-Hsiung Lin, MD Department of Obstetrics and Gynecology College of Medicine National Taiwan University Taipei, Taiwan, Republic of China REFERENCES 1. Su IJ, Kuo TT, Liaw YF. Hepatocyte hepatitis B surface antigen. Arch Pathol Lab Med 1985; 109:400-2. 2. Lin HH, Lee TY, Chen DS, et al. Transplacental leakage of HBeAg-positive maternal blood as the most likely route in causing intrauterine infection with hepatitis B virus. J Pediatr 1987;111:877-81.

Reply To the Editors: With reference to your letter and your comments on my article, I would like to point out the following: We carried out positive controls on the sections obtained by liver biopsies of persons affected with acute viral hepatitis B, surely positive to the antigen. We regret that we omitted this detail from the material and methods section. In the Comment section we wanted to point out the presence of IgM in the babies born to HBsAg carrier mothers. This is also mentioned in the literatllre hilt we did not intend to consider it as a general rule. In the meantime we have enlarged our field of research to other cases of carrier mothers. Echographic data give no evidence of retroplacental hematoma (i.e., that maternal blood mixes with fetal blood). We focused our attention on the presence of viral antigen in definite placental cytotypes that belong to the fetal compartment. Among these cytotypes that appear especially involved are the elements of the phagocytarian system (MPs). In our opinion this shows an active response of placental defence structures to the extraneous agent and suggests that the neonatal hepatitis depends on the immunoreply of placental structures and of the baby itself. I hope that my reply has been exhaustive enough. With great interest I read the results you were able to obtain from your researches and, if possible, I would like to be kept informed of your new findings. Giovanna Lucifora, MD Via San Corrado Complesso INCAM Palazzina A Messina, Italy 98100