DOI: https://doi.org/10.21203/rs.3.rs-2654593/v1
Background: Worldwide, tuberculosis (TB) remains an important cause of maternal mortality and morbidity, accounting for approximately one-third of annual deaths. Moreover, untimely TB treatment during pregnancy increases the risk of perinatal complications and poor fetal prognosis. Recently, there has been widespread use of in vitro fertilization and embryo transfer (IVF-ET). However, its clinical characteristics and possible mechanisms of TB infection in pregnant women who conceive by IVF-ET remain unclear. Therefore, we report three cases of young pregnant women diagnosed with TB after IVF-ET and describe their diagnosis and treatment.
Case presentation: Three young women (age: 26–31 years) diagnosed with primary infertility underwent IVF-ET treatment. They lacked a history of TB or manifestations of activated TB before transplantation. After presenting with fever, cough, and headache at 5–12 weeks of pregnancy, they were diagnosed with miliary TB, disseminated TB, and tuberculous meningitis, respectively. Initially, the patients were on a daily fixed-dose combination of first-line anti-TB treatment (ATT), which comprised rifampicin, isoniazid, pyrazinamide, and ethambutol, followed by medication adjustment during treatment for 6–12 months. Although all fetuses were lost, the patients achieved optimal outcomes after timely ATT.
Conclusions: This report demonstrates the increased risk of TB in pregnant women who conceive by IVF-ET. Therefore, it is important to carefully monitor these women even if they lack a history of or exposure to TB. Accordingly, prompt diagnosis and treatment of TB in these patients is necessary to optimize patient outcomes.
Tuberculosis (TB) is a communicable disease caused by Mycobacterium tuberculosis (Mtb) that is associated with high morbidity and mortality rates. Annually, there are over 9 million new cases and 1 million deaths [1], which mostly occur in developing countries[2]. Over the past three years, there has been an increase in TB-related deaths due to reduced access to TB diagnosis and treatment in the face of the COVID-19 pandemic [3]. Accordingly, it is important to focus on both novel and established infectious diseases during this period.
TB is among the three leading mortality causes among women aged 15–45 years, especially in developing countries[4]. Worldwide, adult women accounted for 33% of all TB cases in 2020 [3]. A study on pregnant women aged 15–49 years reported a significantly increased risk of active TB during pregnancy and postpartum [5]. With the development of assisted reproductive technology (ART), many infertile women prefer to conceive through in vitro fertilization and embryo transplantation (IVF-ET) [6]. IVF-ET is an effective treatment technique for infertility that involves extracting oocytes from an infertile woman, fertilizing them in vitro, and transferring the fertilized eggs into the patient’s uterine cavity[7]. Additionally, adequate exogenous progesterone support in these patients improves the implantation rate and promotes embryonic development, which in turn increases the pregnancy rates [8]. There is a higher risk of TB with pregnancy after IVF-ET than that with natural pregnancy [9]. However, the clinical characteristics of pregnant women who conceive through IVF-ET remain unclear. Therefore, further research is warranted to facilitate accurate and prompt diagnosis and treatment of TB during pregnancy after IVF-ET.
Recently, we encountered several cases of TB infection in pregnant women after IVF-ET in clinical practice. This article describes the cases as well as the mutual relationships and interactions among IVF-ET, pregnancy, and TB. Additionally, we describe the diagnosis and treatment of TB during pregnancy. This article could assist in treatment decisions by clinicians handling these patients.
A 31-year-old woman with a twin pregnancy experienced fever, dry cough, and colporrhagia 5 weeks after embryo transfer. After the symptoms had persisted for 2 months, she was transferred to our hospital on January 13, 2017. She denied any history of exposure to or infection with TB; moreover, she had undergone four IVF-ET treatments for inflammation-induced oviduct obstruction.
Baseline vital parameters were as follows: blood pressure, 101/64 mmHg; pulse, 134/min; respiratory rate, 42/min; and body temperature, 40°C. The patient presented with cyanosis and shortness of breath, with vesicular breath sounds under the lung fields on auscultation. Arterial blood gas analysis revealed type I respiratory failure and respiratory alkalosis. Table 1 shows the important laboratory results during hospitalization. Serum and sputum cultures were negative for bacteria, fungi, and viruses. Chest radiography (Fig. 1. a) revealed diffuse reticular nodules; moreover, chest computed tomography (CT, Fig. 1.c) revealed bilateral diffuse ground glass shadows and miliary nodules as well as spotted calcification in the upper left lung, which was consistent with miliary TB. Further examination showed that the interferon-gamma test was positive. The tuberculin purified protein derivation test was strongly positive. However, bronchoalveolar lavage was negative for acid-fast bacilli. General assessment revealed no extrapulmonary TB locations. International guidelines established by the American Thoracic Society recommend that patients with TB who are etiologically negative but have positive clinical/radiographic findings should receive standard anti-TB therapy (ATT) [10]. Accordingly, she was started on five-drug ATT, which included isoniazid (INH, 0·3 g/day), rifampicin (RIF, 0·45 g/day), pyrazinamide (PZA, 1·5 g/day), and ethambutol (EMB, 0·75 g/day) plus moxifloxacin (Mfx, 0·4 g/day).
| Characteristic | Patient 1 | Patient 2 | Patient 3 | |
|---|---|---|---|---|
| Summary of features | Age(years) | 31 | 30 | 26 |
| Onset time of symptoms at pregnancy(weeks) | 5 | 12 | 11 | |
| TB1history | Denial of TB1 history | Denial of TB1 history | Close exposure to TB1* | |
| Onset manifestation | Fever, dry cough and colporrhagia | Fever, headaches and cough | Fever, headaches, double vision, and shortness of breath | |
| Diagnosis | Miliary pulmonary TB1 | Disseminated TB1 | Tuberculous meningitis | |
| Outcomes for fetus | Spontaneous abortion | Spontaneous abortion | Spontaneous abortion | |
| Abortion time at pregnancy(weeks) | 16 | 16+ 3 | 15 | |
| Pregnancy outcomes for pregnant women | Cured | Cured | Cured | |
| Laboratory results (First day of admission) | WBC (× 109/L) (3.5–9.5) | 5.5 | 6.1 | 4.9 |
| Hb(g/L) (115–150) | 83 | 97 | 119 | |
| PLT (× 109/L) (125–350) | 212 | 290 | 194 | |
| N% (40–75) | 85.5 | 89.1 | 69.5 | |
| ALT(U/L) (20–50) | 32.6 | 16.5 | 35.5 | |
| AST(U/L) (13–35) | 98.7 | 33.3 | 33 | |
| TB2(µmol/L) (1.7–17.1) | 14.9 | 2.1 | 7.9 | |
| A(g/L) (40–55) | 25.9 | 25.5 | 34.3 | |
| K+(mmol/L) (3.5–5.3) | 3.49 | 3.44 | 3.9 | |
| CRP (mg/L) (0–8) | 41.3 | NA | NA | |
| ESR (mm/h) (0–26) | 16 | 54 | 45 | |
| PCT (ng/ml) (< 0.05) | < 0.05 | 0.17 | < 0.05 | |
| TB1-related | T-SPOT.TB | + | + | + |
| PPD test | +++ | NA | NA | |
| Xpert MTB/RIF | NA | +(CSF) | +(CSF) | |
| Sputum culture | – | NA | NA | |
| Blood culture | – | – | – | |
| CSF culture | NA | – | – | |
| Cervical secretions culture | NA | Mtb, Prevotella bivia | NA | |
| Acid-fast staining | NA | + (cervical secretions) | +(CSF) | |
| NA = Not available. +=positive. –=negative.TB1 = tuberculosis. WBC = white blood cell. Hb = hemoglobin. PLT = platelet. N%= percentage of neutrophils. ALT = alanine aminotransferase. AST = aspartate aminotransferase. TB2 = total bilirubin. A = albumin. K+= serum potassium ions. CRP = C-reactive protein. ESR = erythrocyte sedimentation rate. PCT = procalcitonin. T-SPOT.TB = Tuberculous infection of T cell spot test. PPD = purified protein derivative. Mtb = Mycobacterium tuberculosis; CSF = cerebrospinal fluid. | ||||
| *The father of Case 3 infected with TB and was cured after ATT 10 years ago. | ||||
After approximately 1 week of ATT, there was a decrease in the patient’s maximum body temperature (Fig.S1) and an improvement in blood oxygen saturation. Chest radiography (Fig. 1. b) and CT (Fig. 1. d) showed improvement in diffuse, bilateral, and discrete miliary nodules on week 3 of ATT. At 16 weeks of pregnancy, vaginal bleeding worsened and she underwent induced abortion. Meropenem (Mem) was used to prevent intrauterine infections. Owing to severe liver damage, RIF and PZA were discontinued and replaced with linezolid (Lzd) and rifapentine (Rpt). However, Lzd was discontinued because of frequent vomiting. Fig.S1 shows the changes in clinical symptoms and the highest body temperature with adjustment of antibiotics during hospitalization.
The patient was discharged home on February 22 with a follow-up appointment in specialized TB hospitals. She was maintained on treatment with oral INH (0·3 g/day), EMB (0·75 g/day), Rpt (0·45 g, twice a week), and levofloxacin (0·5 g/day) for approximately 6 months. The patient was completely cured without sequelae and she underwent IVF-ET again without any additional complications. Finally, she gave birth to a healthy son.
A 30-year-old housewife conceived by IVF-ET owing to a fallopian tube obstruction. At 12 weeks of pregnancy, the patient began experiencing persistent headaches, cough, and sputum with low-grade fever (37·5℃–38·5℃). She denied a history of TB or exposure to TB. During pregnancy, she received 10 mg of oral dydrogesterone. At 16 gestation weeks, she was admitted to our hospital with extreme thinness, unclear consciousness, and positive meningeal stimulation. Additional examination revealed vesicular breath sounds under the lung fields on auscultation, a full abdomen with left-upper tenderness, and slight colporrhagia.
Table 1 shows important laboratory results at admission. The T-SPOT. TB test was highly positive for ESAT-6 and CFP-10, with both having test values > 50 (reference normal value: < 6). The cerebrospinal fluid (CSF) was slightly turbid in appearance, with an opening pressure of 230 mmH2O, polykaryocyte predominance (80%), hypoglycorrhachia (1·98 mmol/L), proteinorachia (0·66 g/L), and lower chloride (119·8 mmol/L), which was consistent with TB meningitis (TBM). Examination using Xpert MTB/RIF Ultra confirmed Mtb in the CSF, without evidence of RIF resistance. There were no organisms in the CSF on the Gram stain, Ziehl–Neelsen stain, or ink stain tests. Blood and CSF cultures were negative for bacteria and fungi. Additionally, microscopic examination of acid-fast bacilli in cervical secretions revealed positive results; moreover, Mtb and Prevotella bivia were cultivated in cervical secretions. Chest and abdominal CT revealed bilateral diffuse miliary nodules as well as diffuse peritoneal and mesenteric thickening, which further supported the diagnosis of acute miliary TB and TB peritonitis. Brain magnetic resonance imaging (MRI) revealed multiple abnormal signal foci, which suggested that TB encephalitis was more likely.
Accordingly, the patient was diagnosed with disseminated TB. She was started on ATT, which comprised INH (0·6 g qd), RIF (0·45 g qd), PZA (1·5 g qd), EMB (0·75 g qd), and streptomycin (0·75g qd). On the third day of admission, the patient presented with persistent fever (up to 40°C) and heavy vaginal bleeding, which was diagnosed as an inevitable miscarriage. Accordingly, she urgently underwent pregnancy termination. Metronidazole tablets (500 mg) were administered thrice daily to prevent postpartum intrauterine infection. The condition of the patient further deteriorated and she was transferred to a TB specialist hospital on January 10.
Despite her serious illness, we learned that the patient was recovering well and had discontinued TB-related drugs one and a half years after discharge.
A 26-year-old woman who presented with fever accompanied by headaches, double vision, and shortness of breath at 11 weeks of pregnancy conceived by IVF-ET. Ten years ago, the patient’s father had been infected with TB and had been treated using ATT. Physical examination revealed a clear consciousness, normal limb muscle strength, normal muscle, positive Babinski's reflex, and positive meningeal stimulation. The other physical observations were unremarkable.
After admission, the patient's body temperature fluctuated between 38°C and 40°C (Fig. S2). Table 1 shows the laboratory results during hospitalization. No organisms were detected in the blood, bone marrow, and CSF. There were positive results in the interferon-gamma release assay. The CSF of the first spinal tap showed a light-yellow turbid appearance and an opening pressure of > 500 mmH2O. CSF analysis revealed polynucleosis, reduced glucose levels (0·89 mmol/L), reduced chlorine levels (104·8 mmol/L), and remarkably increased protein levels (2·69 g/L) (Table S1). Moreover, biochemical analyses revealed a substantial increase in the levels of adenosine deaminase (11·4 U/L) and lactate dehydrogenase (408 U/L (Table S1). Lumbar CSF was positive for Mtb through acid-fast staining and the X-pert assay, with no evidence for RIF resistance. Brain MRI revealed nodules in the anterior horn of the left ventricle and multiple intracranial pial enhancements, which was consistent with TB infection (Fig. 2).
All these test results led to the clinical diagnosis of TBM. RIF (0·45g/d), INH (0·9g/d), PZA (1·5g/d), and EMB (0·75g/d) were used as an ATT. The patient underwent four-drug chemotherapy; however, she still presented fever (Fig.S2). Therefore, Mem (6 g/d, June 7 to June 14) was used for TBM treatment since it penetrated the blood–brain barrier [11]. Subsequently, the temperature gradually normalized. Repeated lumbar punctures showed dynamic fluctuations in the intracranial pressure, protein levels, chlorine, and the proportion of multinucleated cells (Table S1). CSF protein was still at a high level; therefore, Lzd (1·2g/d) was added to the TB therapy on June 23. The patient was discharged on June 24 upon request by her family.
We learned that the patient experienced an inevitable miscarriage one week after discharge. Follow-up lung and brain CT scans at 1 year after diagnosis revealed complete regression of all lesions as well as normal liver and kidney function, without pregnancy. The patient is still undergoing RIF, EMB, and Mfx at the latest follow-up in July 2022.
Our study reports three cases of young pregnant women diagnosed with TB after IVF-ET and describes their diagnosis and treatment. During the COVID-19 pandemic, established diseases have led to unprecedented consequences on the health of individuals of all ages. TB remains the leading mortality cause among women of childbearing age [12] and is a common non-obstetric cause of maternal mortality responsible for approximately one-third of deaths in developing countries[13]. Globally, approximately 216,500 pregnant women have active TB[12]. However, the characteristics of TB during pregnancy after IVF-ET treatment remain unclear. Therefore, there is a need to focus on prompt diagnosis and treatment of TB, especially with respect to frail or immunocompromised patients.
During pregnancy, there is an increased susceptibility to TB, which is attributed to related immune and endocrine disorders. A prospective longitudinal study[14] on singleton pregnancies reported decreased expression of Th1-associated cytokine expression over the pregnancy course, which facilitates tolerance to the fetal allograft and promotes pregnancy to term. However, Th1 cells produce interleukin 2 and interferon-gamma to confer protection against mycobacterial infection [15]. During the pregnancy course, there is a significant gradual decrease in tumor necrosis factor (TNF)-α secretion by natural killer cells [16]. There is an increased risk of TB activation after treatment with TNF-α inhibitors [17, 18], which demonstrates the importance of TNF-α in containing Mtb infections. Accordingly, cytokine changes during pregnancy increase the risk of TB infection. Hormonal changes during pregnancy, especially in estrogen, progesterone, and human chorionic gonadotropin, inhibit the immune function of lymphocytes and reduce the mother’s immunity [19]. Therefore, the bidirectional interaction between hormones and the immune system could contribute to the increased incidence rates of infection during pregnancy. Our study reports three cases of women diagnosed with TB after IVF-ET; among them, two cases showed TBM as a complication. Increased microvascular permeability after pregnancy facilitates the entry of Mtb into the bloodstream, which increases the risk of miliary and even central nervous system TB[20, 21].
In 2020, in the ranking of countries with a high burden of new TB cases, China (8·5%) ranked second after India (26%)[3]. With the announcement of the three-child policy by the Chinese government, there has been increasing demand for ART. IVF allows infertile couples to have a baby; however, it involves steps that differ greatly from those of natural pregnancy. A large proportion of infertile patients undergoing IVF present with occult genital TB (GTB)[22]. Compared with healthy women, women with GTB have poor ovarian reserves and require higher doses of exogenous gonadotropins for ovulation induction, which in turn facilitates the dissemination and reproduction of M. tuberculosis [23]. In addition, lymphocyte function inhibition due to the use of progesterone[24] and glucocorticoids [25, 26] during IVF-ET therapy may increase the risk of TB infection and reactivation. A Chinese study showed that the incidence of miliary TB was significantly higher in IVF-ET patients than in naturally pregnant patients (41·38% vs. 24·44%)[9]. In our study, cases 1 and 2 underwent IVF owing to inflammation-induced oviduct obstruction, while case 3 had a clear history of exposure to TB (Table 1). There was no direct evidence of TB symptoms or signs before IVF-ET. However, China is estimated to have the highest latent TB infection (LTBI) burden globally, with approximately 350 million infections[27]. A modeling study suggested that most TB cases in China are currently resulting from LTBI [28]. Therefore, the three patients may have had LTBI before IVF-ET, which was activated after conception. Notably, active TB in pregnancy could be a result of LTBI activation/progression; however, there remains no definitive evidence. Therefore, screening for LTBI before and during pregnancy may facilitate prevention.
Obstetricians and community health care workers should ensure accurate diagnosis of TB before or during pregnancy through insidious symptoms. Generally, in China, routine prenatal screening is performed for infectious diseases such as human immunodeficiency virus, syphilis, and hepatitis B virus; however, it is not universal for TB [29]. Contrastingly, in the UK, there is early organized screening for pulmonary TB during pregnancy [30]. We believe that routine TB screening before pregnancy should be considered by public health bodies worldwide. Specifically, the history of or exposure to TB should be investigated in detail, especially before IVF. In addition, TB-related examinations, including purified protein derivative tests, sputum TB smears, TB polymerase chain reaction tests, and T-spot tests [31], should be promptly performed to screen for TB before embryo implantation. If necessary, histopathological examination through laparoscopy or hysteroscopy can be used to exclude GTB in women with primary infertility from regions with a high TB incidence [22]. Among patients with a high suspicion of TB, in case of negative conventional TB tests, metagenomic next-generation sequencing (mNGS) of various body fluids, including alveolar lavage fluid, serum, ascites, and CSF, could facilitate precision diagnosis and tailored therapy for clinical infectious diseases. Compared with traditional cultures, mNGS is superior with respect to identifying rare infectious pathogens, especially M. tuberculosis[32]. We advocate routine tuberculin tests before IVF in patients with possible exposure to TB or oviduct obstruction. Additionally, dynamic monitoring should be performed during pregnancy to identify TB activation.
TB among pregnant women is of public health importance given the mortality and morbidity risk to the mothers, as well as the potential harm to the fetus or neonates. In our case, all three patients underwent abortion during the second pregnancy trimester. Most spontaneous abortions occur at 13–16 weeks after embryo transfer, which mainly result from severe TB toxemia and chorioamnionitis due to the spread of M. tuberculosis through the blood to infect the placenta, resulting in abortion and fetal death[33]. Untimely TB treatment during pregnancy increases the risk of perinatal complications, including preeclampsia, intrauterine growth delay, prenatal bleeding, low birth weight, low Apgar score at birth, and early fetal death [25]. In our study, although all fetuses died, all the patients were cured after timely ATT. At follow-up, one patient successfully conceived after a second IVF-ET. Therefore, early diagnosis followed by timely ATT helps ensure the optimal outcomes of TB in pregnancy for both mother and infant, even for vicious disseminated TB.
Our study has several limitations. First, we only included three individuals from a single center. The mechanisms underlying the association of ART with the activation and hematogenous spread of TB remain unclear. Therefore, more in-depth research from clinical cohorts and laboratories with greater scientific rigor is needed. Second, we asked the patients whether they had LTBI before pregnancy through follow-up telephone interviews, which might have led to a recall bias in the diagnosis.
This report demonstrates the increased risk of TB in pregnancy after IVF-ET; therefore, it is important for clinicians to carefully consider such patients, even in the absence of a history of TB. It is important to strive for prompt diagnosis and treatment of TB in order to optimize patient outcomes.
TB: tuberculosis; Mycobacterium tuberculosis: Mtb; ART: assisted reproductive technology ;IVF-ET: in vitro fertilization and embryo transfer; ATT: anti-TB treatment; CT: computed tomography；INH: isoniazid; RIF: rifampicin; PZA: pyrazinamide; EMB: ethambutol; Mfx: moxifloxacin; Mem: Meropenem; Lzd: linezolid; Rpt: rifapentine; CSF: cerebrospinal fluid; TBM: TB meningitis; MRI: magnetic resonance imaging; TNF: tumor necrosis factor; GTB: genital TB; LTBI: latent TB infection; mNGS: metagenomic next-generation sequencing.
Ethics approval and consent to participate
Ethics approval was obtained from Xiangya Hospital, Central South University. Written informed consent was obtained from the participants for the publication of this case report (including all data and images).
Consent for publication
All authors have read and approved the manuscript. Written informed consent was obtained from the participants for the publication of this case report.
Availability of data and materials
Data sharing is not applicable to this article as no datasets were generated or analyzed during the current study.
Competing interests
We declare that we have no competing interests.
Funding
This work was supported by grants from the National Natural Sciences Foundation of China [grant numbers 82070613, 81970550], the National Natural Sciences Foundation of Hunan Province [grant number 2019JJ30041)], the National Major Science and Technology Projects (grant numbers 2018ZX10302206, 2018ZX10723203], and the Innovation-Driven Project of Central South University [grant number 2020CX044].
Authors' contributions
RC conceived the work. JZ and JL searched the literature and wrote the draft of this manuscript and contributed equally to this work. JZ, JL, and CC collected and interpreted the data. All authors revised the manuscript critically. All authors had full access to all study data, read the manuscript, and approved the final version for submission.
Acknowledgements
Not applicable.