Human Reproduction, Vol. 15, No. 1, 66-71,
January 2000
© 2000 European Society of Human Reproduction and Embryology
Relationships of serum pro-inflammatory cytokines and vascular endothelial growth factor with liver dysfunction in severe ovarian hyperstimulation syndrome
Department of Obstetrics and Gynecology, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan
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Abstract |
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The aims of this study were to determine if differences in serum pro-inflammatory cytokines, vascular endothelial growth factor (VEGF) and clinical pregnancy rate, could be observed in women with severe ovarian hyperstimulation syndrome (OHSS) in those who did and did not have liver dysfunction. Twenty-nine in-vitro fertilization patients with severe OHSS were included. The patients were divided into the normal liver function tests (LFT) group (n = 14) and the abnormal LFT group (n = 15) according to the LFT on day of admission. Periodic measurements of serum interleukin (IL)-6, IL-8, tumour necrosis factor-
(TNF-), VEGF, oestradiol, progesterone concentrations, and LFT were performed during hospitalization. Concentrations of IL-6 in the active phase of OHSS were significantly higher in the abnormal LFT group than in the normal LFT group (19.7 ± 15.7 versus 8.1 ± 7.0 pg/ml, respectively). The severity of liver dysfunction was not correlated with concentrations of oestradiol, progesterone, haematocrit, white blood cell counts, or any studied cytokine. The clinical pregnancy rate was significantly lower in the abnormal LFT group (46.7%) than in the normal LFT group (85.7%). These results suggest that IL-6 cytokine system may play a role in the pathogenesis of liver dysfunction in severe OHSS. Abnormal LFT were associated with lower clinical pregnancy rates.
Key words: cytokine/interleukin-6/liver dysfunction/ovarian hyperstimulation syndrome/vascular endothelial growth factor
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Introduction |
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Ovarian hyperstimulation syndrome (OHSS) is a relatively common complication of ovarian stimulation, and can be life threatening. In severe cases, a critical condition develops with massive ascites, marked ovarian enlargement, pleural effusion, electrolyte imbalance, and hypovolaemia with hypotension and oliguria (Schenker and Weinstein, 1978
). The underlying mechanism responsible for the clinical manifestations of OHSS appears to be an increase in capillary permeability of the mesothelial surface with acute fluid shift out of the intravascular space (Polishuk and Schenker, 1969).
Recent observations provide evidence for hepatic disturbance in the most severe form of OHSS (Sueldo et al., 1988; Younis et al., 1988; Balasch et al., 1990; Ryley et al., 1990; Nawroth et al., 1996; Shimono et al., 1998; Tortoriello et al., 1998). Abnormal liver function tests (LFT) were recorded in 37.5% (3/8) patients with severe OHSS in a European series (Forman et al., 1990). The mechanism of elevated LFT in severe OHSS remains unclear. The proposed mechanisms include increased circulating sex steroid concentrations (Younis et al., 1988; Balasch et al., 1990), hepatocellular damage from the increased vascular permeability that characterizes severe OHSS (Wakim and Fox, 1996), and consequences of hepatic ischaemia/reperfusion (Simpson et al., 1997) as a result of circulatory dysfunction in severe OHSS (Balasch et al., 1998).
Pro-inflammatory cytokines [e.g. interleukin (IL)-6, IL-8, and tumour necrosis factor- (TNF-)] and vascular endothelial growth factor (VEGF) have been implicated as mediators in the pathogenesis of capillary leakage in OHSS (Friedlander et al., 1993; McClure et al., 1994; Abramov et al., 1996). Pro-inflammatory cytokines have also been reported to be involved in the acute phase response to hepatic injury (Moshage, 1997). Furthermore, serum VEGF has been reported to be involved in hypoxia-related angiogenesis occurring in various liver diseases (Akiyoshi et al., 1998). Therefore, it was postulated that pro-inflammatory cytokines and VEGF might be involved in the pathogenesis of liver dysfunction in severe OHSS. If factor(s) that cause liver dysfunction in severe OHSS also lead to a hostile environment for implantation, reduced pregnancy rates should be observed in women with abnormal LFT.
The current study was designated to examine whether differences in serum pro-inflammatory cytokine and VEGF concentrations, as well as the clinical pregnancy rate, could be observed in women with severe OHSS in those who did and did not have liver dysfunction.
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Materials and methods |
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Subjects and in-vitro fertilization protocols
Patients included in the present study were 33 consecutive in-vitro fertilization (IVF) patients with severe OHSS, who were hospitalized for management. The diagnosis of severe OHSS was based on the classification proposed (Schenker and Weinstein, 1978
). All patients had had normal LFT at the time of oocyte retrieval. Baseline laboratory assessments of the patients on admission included complete blood counts, electrolytes, coagulation profile, and standard liver and renal function tests. When abnormal LFT were noted, serological screening for hepatitis A, B, and C, herpes simplex virus, Epstein–Barr virus and cytomegalovirus were performed to exclude recent viral infection. Hepatic imaging by ultrasound was performed to exclude possible biliary tract pathology. Non-steroidal anti-inflammatory agents or acetylsalicylic acid were not used during the period of observation in any of the patients. Periodic LFT [total and direct bilirubin, alkaline phosphatase, AST (aspartate aminotransferase), ALT (alanine aminotransferase), 
-GT (gamma-glutamyl transpeptidase), lactate dehydrogenase (LDH), and albumin] were performed at intervals of 3–5 days during hospitalization. One woman with positive hepatitis B surface antigen and three patients, whose liver dysfunction developed several days after hospitalization, rather than at the time of admission, were excluded from the study. Overall, the remaining 29 patients were divided into the normal LFT group (n = 14) and the abnormal LFT group (n = 15) according to the LFT on admission.
The ovarian stimulation protocols were performed as previously described (Chen et al., 1997).
Monitoring and management of the patients during hospitalization
Monitoring of the patients included daily measurement of body weight, abdominal girth, fluid intake and urine output, and periodic ultrasound assessment as well as routine blood parameter measurements (complete blood counts, electrolytes, liver and renal function tests) at intervals of 3–5 days. Additional blood was drawn for oestradiol, progesterone, and cytokine assays. The blood samples were centrifuged for 10 min at 400 g, and the serum was stored immediately at –70°C before assay for cytokines and steroids. Abdominal paracentesis for tense ascites and thoracentesis for massive pleural effusion were performed as needed (Chen et al., 1998).
To describe the clinical course of OHSS, all measurements were normalized to the day of pre-ovulatory human chorionic gonadotrophin (HCG) administration (day 0). Furthermore, to correlate the concentrations of various cytokines and abnormal LFT with changes in symptoms or disease severity, the hospital stay was divided from the day of admission day to the day of spontaneous diuresis into three periods. The day of spontaneous diuresis was defined as the day that fluid balance shifted from a positive fluid balance to a negative fluid balance during the resolution stage of OHSS. This day was identified by reviewing the medical records of fluid intake and output throughout the course of hospitalization. The period from the day of spontaneous diuresis to the day of discharge was termed period 4.
The four periods were taken to represent different time phases of the course of OHSS. While periods 1 and 2 represented the active phase of disease, periods 3 and 4 represented the resolution phase and clinical convalescence of OHSS. There were 17, 13, nine and 15 serum samples respectively in the four periods of OHSS in the normal LFT group and 17, 12, 11 and 13, respectively in the abnormal LFT group. Data within each period were pooled for statistical analyses.
Cytokines and hormone assays
Concentrations of cytokines (IL-6, IL-8 and TNF-) and VEGF were measured by solid-phase enzyme-linked immunosorbent assay using commercially available kits (Quantikine; R&D System, Inc., Minneapolis, MN, USA). The sensitivity of these cytokine assays was 1 pg/ml for IL-6, 5 pg/ml for TNF- and VEGF, and 10 pg/ml for IL-8. All samples were run in duplicate and were assayed at the same time to avoid inter-assay variations and possible alterations due to freezing and thawing.
Serum oestradiol and progesterone concentrations were assayed using a chemiluminescent immunoassay (Immulite; Diagnostic Products Corporation, Los Angeles, CA, USA). The intra-assay and inter-assay coefficients of variation for oestradiol at a concentration of 480 pg/ml were 6.3 and 6.4% respectively, and 10.5 and 8.1% for progesterone at a concentration of 7.2 ng/ml.
Statistical analysis
Results are expressed as means ± SD. Statistical analyses were performed using Student's t-test, Fisher's exact test, the Mann–Whitney test and Kruskal–Wallis test as appropriate. Correlation analysis was carried out using Spearman correlation coefficients. Statistical significance was defined as a value of P < 0.05. Statistical analysis was performed with the Statistical Package for the Social Sciences (version 9.0, SPSS Inc., Chicago, IL, USA).
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Results |
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The clinical and laboratory data between normal and abnormal LFT groups are presented in Table I
. There were no significant differences in any studied parameters, except for the clinical pregnancy rate and the implantation rate, which were significantly lower in the abnormal LFT group than in the normal LFT group.
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Table II
shows the frequency of abnormal LFT at the onset of severe OHSS. The abnormalities in the LFT had returned to normal values in only three of 15 patients (20%) at the time of discharge. However, they returned to normal values in all patients during the subsequent outpatient follow-up. The duration of abnormal LFT ranged from 5 to 32 days. Liver biopsy was not performed in any of the patients.
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Figure 1
shows the concentrations of ALT and AST in the abnormal LFT group and serum oestradiol concentrations, haematocrit, and white blood cell (WBC) counts in the normal and abnormal LFT groups during the four periods of OHSS. The haematocrit concentrations and WBC counts fell significantly during hospitalization in both groups (haematocrit, P < 0.001 in both groups; WBC counts, P < 0.001 in the normal LFT group and P = 0.005 in the abnormal LFT group, Kruskal–Wallis test). Concentrations of oestradiol showed no significant difference during the four periods of OHSS in either group. There were no significant differences in oestradiol concentrations or WBC counts when the two groups were compared in any period of OHSS, except for the haematocrit concentrations in period 4 (P = 0.047 by the Mann–Whitney test).
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) and AST (
) in the abnormal LFT group, and (B) serum oestradiol, (C) haematocrit (HCT), and (D) WBC counts in the normal (•) and abnormal LFT (
) groups during the course of ovarian hyperstimulation syndrome (OHSS). Data represent the mean ± SEM. The horizontal dashed line represents the upper normal limit of ALT and AST. *P = 0.047 by the Mann–Whitney test. ALT = alanine aminotransferase; AST = aspartate aminotransferase; LFT = liver function tests; WBC = white blood cell.ALT and AST concentrations were correlated with concentrations of various cytokines, sex steroids, haematocrit, and WBC counts in the abnormal LFT group. Concentrations of ALT correlated with those of AST (r = 0.857, n = 48, P < 0.001). However, concentrations of ALT or AST did not correlate with those of oestradiol, progesterone, haematocrit, WBC counts, or any studied cytokine.
Figure 2 shows changes in serum cytokine concentrations during the four periods of severe OHSS in the normal and abnormal LFT groups. Concentrations of IL-6 in period 1 (active phase) of OHSS were significantly higher in the abnormal LFT group [19.7 ± 15.7 (mean ± SD) versus 8.1 ± 7.0 pg/ml, respectively; P = 0.01 by the Mann–Whitney test].
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In order to evaluate whether serum pro-inflammatory cytokine and VEGF concentrations could have played a role in the diminished implantation rate in those who had abnormal LFT, the abnormal LFT group was further subdivided into two subgroups: those with implantation failure (n = 8) (including conception failure, chemical pregnancy, and first trimester abortion) and those with implantation success (n = 7) (pregnancy exceeding 13 weeks of gestation), and compared concentrations of various cytokines during the active phase (period 1) of OHSS between the two subgroups. There was no significant difference in concentrations of any studied cytokine between the two subgroups. However, the haematocrit concentrations were significantly higher in patients with implantation failure than those with implantation success (43.9 ± 5.2 versus 38.6 ± 5.3%, respectively; P = 0.027 by the Mann–Whitney test).
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Discussion |
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The findings of this study suggest that IL-6 may play a role in the pathogenesis of abnormal LFT in severe OHSS. Interleukin-6, along with IL-1 and TNF-
, mediates systemic reactions characterized by leukocytosis, increased vascular permeability and increased concentrations of acute phase proteins synthesized by the liver (Moshage, 1997). Increased circulating IL-6 has been reported in patients with severe alcoholic hepatitis (Sheron et al., 1991). Similar elevations in plasma IL-6 were found in sepsis (Martin et al., 1994) and fulminant hepatic failure (Wigmore et al., 1998), perhaps reflecting common disease mechanisms. Animal study (Wang et al., 1997) has shown that pro-inflammatory cytokines such as IL-6 and TNF- are up-regulated before the occurrence of hepatocellular dysfunction during early sepsis and may be responsible for hepatocellular dysfunction. However, the potential pathogenic role of elevated circulating IL-6 in the development of hepatic injury needs further clarification.
The clinical significance of elevated LFT in severe OHSS has not yet been thoroughly investigated. Conceivably, factor(s) that cause liver dysfunction in severe OHSS may also provoke a hostile environment that leads to implantation failure. Clinical pregnancy rates in women with severe OHSS after IVF have recently been reported to be 73.2% in a multicentre study (Abramov et al., 1998). Workers in a European series (Forman et al., 1990) observed liver dysfunction in three of eight (37.5%) patients with severe OHSS. The pregnancy in one of them ended in intrauterine death 60 days after oocyte retrieval, but the outcome in the other two patients with liver dysfunction was not mentioned. Instead, they showed the pregnancy outcome in these eight OHSS patients including five live births (62.5%), two miscarriages (25%), and one conception failure (12.5%). In the present study, it was found that the clinical pregnancy rate was significantly lower in the abnormal LFT group (46.7%) than in the normal LFT group (85.7%), suggesting that an abnormal LFT is associated with a lower clinical pregnancy rate.
Table III summarizes the pregnancy outcome of reported cases of abnormal LFT with OHSS. One-third of patients (3/9) did not conceive, one-third experienced early miscarriage, and only one-third of patients had an uneventful pregnancy course. Patients with severe OHSS are exposed to a variety of insults that potentially affect early pregnancy. Haemodynamic instability, hypoxaemia, and liver and renal dysfunction are potential offensive mechanisms (Abramov et al., 1998). Further, patients with severe OHSS are exposed to extremely high endogenous oestrogen concentrations, in addition to cytokines (Abramov et al., 1996) and possibly the renin–angiotensin system (Navot et al., 1987), the effects of which on an early pregnancy are unknown. Whether the presence of an abnormal LFT in severe OHSS is associated with a higher miscarriage rate and a diminished pregnancy potential remains to be elucidated.
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This study had limitations. Firstly, the study only included patients with severe OHSS and excluded patients with all lesser stages of disease. Thus, it is difficult to make any conclusion about OHSS as a whole. Indeed, elevated LFT in a woman with moderate OHSS has been reported recently (Wakim and Fox, 1996
). Further studies are warranted to investigate the significance of elevated LFT in patients with mild and moderate OHSS. Secondly, liver biopsies were not performed in any of the patients. Previous liver biopsies (Sueldo et al., 1988; Ryley et al., 1990) have shown ultrastructural changes consistent with increased hepatic enzyme activity. Similar changes are, however, seen in a number of different liver diseases and thus are non-specific. Thirdly, the study may have a type II statistical error because only 29 patients were studied. It would be desirable to increase the number of patients in each arm of the cohort to gain statistical power but this may not have been possible within a reasonable time, given the rarity of severe OHSS. In conclusion, the results of this study suggest that IL-6 cytokine system may play a role in the pathogenesis of liver dysfunction. Clinicians should be aware of the presence of liver dysfunction in severe OHSS. The possible role of abnormal LFT as a prognostic marker for adverse pregnancy outcome in OHSS awaits further clarification.
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Acknowledgments |
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We acknowledge financial support by grant DOH88-HR-841 from the Department of Health, the Executive Yuan and help from the National Health Research Institute of the Republic of China.
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Notes |
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1 To whom correspondence should be addressed at: Department of Obstetrics and Gynecology, National Taiwan University Hospital, 7, Chung-Shan South Road, Taipei, Taiwan
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References |
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Abramov, Y., Elchalal, U. and Schenker, J.G. (1998) Obstetric outcome of in vitro fertilized pregnancies complicated by severe ovarian hyperstimulation syndrome: a multicenter study. Fertil. Steril., 70, 1070–1076.[Web of Science][Medline]
Abramov, Y., Schenker, J.G., Lewin, A. et al. (1996) Plasma inflammatory cytokines correlate to the ovarian hyperstimulation syndrome. Hum. Reprod., 11, 1381–1386.
Akiyoshi, F., Sata, M., Suzuki, H. et al. (1998) Serum vascular endothelial growth factor levels in various liver diseases. Dig. Dis. Sci., 43, 41–45.[Web of Science][Medline]
Balasch, J., Carmona, F., Llach, J. et al. (1990) Acute prerenal failure and liver dysfunction in a patient with severe ovarian hyperstimulation syndrome. Hum. Reprod., 5, 348–351.
Balasch, J., Fábregues, F. and Arroyo, V. (1998) Peripheral arterial vasodilation hypothesis: a new insight into the pathogenesis of ovarian hyperstimulation syndrome. Hum. Reprod., 13, 2718–2730.
Chen, C.D., Wu, M.Y., Yang, J.H. et al. (1997) Intravenous albumin does not prevent the development of severe ovarian hyperstimulation syndrome. Fertil. Steril., 68, 287–291.[Web of Science][Medline]
Chen, C.D., Yang, J.H., Chao, K.H. et al. (1998) Effects of repeated abdominal paracentesis on uterine and intraovarian haemodynamics and pregnancy outcome in severe ovarian hyperstimulation syndrome. Hum. Reprod., 13, 2077–2081.
Forman, R.G., Frydman, R., Egan, D. et al. (1990) Severe ovarian hyperstimulation syndrome using agonists of gonadotrophin-releasing hormone for in vitro fertilization: a European series and a proposal for prevention. Fertil. Steril., 53, 502–509.[Web of Science][Medline]
Friedlander, M.A., Loret de Mola, J.R. and Goldfarb, J.M. (1993) Elevated levels of interleukin-6 in ascites and serum from women with ovarian hyperstimulation syndrome. Fertil. Steril., 60, 826–833.[Web of Science][Medline]
Martin, C., Saux, P., Mege, J.L. et al. (1994) Prognostic values of serum cytokines in septic shock. Intensive Care Med., 20, 272–277.[Web of Science][Medline]
McClure, N., Healy, D.L., Rogers, P.A.W. et al. (1994) Vascular endothelial growth factor as capillary permeability agent in ovarian hyperstimulation syndrome. Lancet, 344, 235–236.[Web of Science][Medline]
Moshage, H. (1997) Cytokines and the hepatic acute phase response. J. Pathol., 181, 257–266.[Web of Science][Medline]
Navot, D., Margalioth, E.J., Laufer, N. et al. (1987) Direct correlation between plasma renin activity and severity of the ovarian hyperstimulation syndrome. Fertil. Steril., 48, 57–61.[Web of Science][Medline]
Nawroth, F., Heinrich, J., Bruns, U. et al. (1996) Severe ovarian hyperstimulation syndrome and icterus. Hum. Reprod., 11, 2441–2442.
Polishuk, W.Z. and Schenker, J.G. (1969) Ovarian overstimulation syndrome. Fertil. Steril., 20, 443–450.[Web of Science][Medline]
Ryley, N.G., Forman, R., Barlow, D. et al. (1990) Liver abnormality in ovarian hyperstimulation syndrome. Hum. Reprod., 5, 938–943.
Schenker, J.G. and Weinstein, D. (1978) Ovarian hyperstimulation syndrome: a current survey. Fertil. Steril., 30, 255–268.[Web of Science][Medline]
Sheron, N., Bird, G., Goka, J. et al. (1991) Elevated plasma interleukin-6 and increased severity and mortality in alcoholic hepatitis. Clin. Exp. Immunol., 84, 449–453.[Web of Science][Medline]
Shimono, J., Tsuji, H., Azuma, K. et al. (1998) A rare case of hepatic injury associated with ovarian hyperstimulation syndrome. Am. J. Gastroenterol., 93, 123–124.[Web of Science][Medline]
Simpson, K.J., Lukacs, N.W., Colletti, L. et al. (1997) Cytokines and the liver. J. Hepatol., 27, 1120–1132.[Web of Science][Medline]
Sueldo, C.E., Price, H.M., Bachenberg, K. et al. (1988) Liver dysfunction in ovarian hyperstimulation syndrome: a case report. J. Reprod. Med., 33, 387–390.[Web of Science][Medline]
Tortoriello, D.V., McGovern, P.G., Colon, J.M. et al. (1998) Critical ovarian hyperstimulation syndrome in a `coasted' in-vitro fertilization patient. Hum. Reprod., 13, 3005–3008.
Wakim, A.N. and Fox, S.D. (1996) Elevated liver function tests in a case of moderate ovarian hyperstimulation syndrome. Hum. Reprod., 11, 588–589.
Wang, P., Ba, Z.F. and Chaudry, I.H. (1997) Mechanism of hepatocellular dysfunction during early sepsis: key role of increased gene expression and release of pro-inflammatory cytokines tumor necrosis factor and interleukin-6. Arch. Surg., 132, 364–370.
Wigmore, S.J., Walsh, T.S., Lee, A. et al. (1998) Pro-inflammatory cytokine release and mediation of the acute phase protein response in fulminant hepatic failure. Intensive Care Med., 24, 224–229.[Web of Science][Medline]
Younis, J.S., Zeevi, D., Rabinowitz, R. et al. (1988) Transient liver function tests abnormalities in ovarian hyperstimulation syndrome. Fertil. Steril., 50, 176–178.[Web of Science][Medline]
Submitted on May 24, 1999; accepted on October 8, 1999.
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