Mycobacterium tuberculosis Infection of the placenta: a study of the early (innate) inflammatory response in two cases

Pathomorphological characteristics of tuberculous placenta and its clinical implication

BACKGROUND

The study of pathologic diagnosis of placental TB is rare. The aim of this study is analyzing the pathomorphological characteristics of tuberculosis (TB) placenta during pregnancy and its clinical significance.

METHODS

Nineteen cases of placental tissue specimens during pregnancy were collected from June 2015 to February 2022 at Shanghai Public Health Clinical Center, the only inpatient center for pregnant women with TB in Shanghai, China. Hematoxylin-eosin staining, acid-fast staining, and molecular testing were applied to analyze them comprehensively in combination with clinical information.

RESULTS

Among the 19 cases, 7 cases caused intrauterine stillbirth, 3 cases received artificial abortion required by the pregnant woman, the other 9 cases received standard delivery and the infants survived, however, 3 of them were low-weight preterm infants, and another 1 case suffered mild intrauterine asphyxia. The 9 surviving infants were followed-up, of which 3 cases got congenital TB. For pathological characteristics of placental tissues under light microscopy, there were 3 cases of epithelioid granuloma formation, 13 cases of acute fetal membranitis, 4 cases of caseous necrosis, 7 cases of inflammatory necrosis, 10 cases of coagulative necrosis, and 6 cases with small focal calcifications. All placental tissues were positive for acid-fast staining and polymerase chain reaction (PCR). Molecular pathological diagnosis showed that 18 cases were positive for Mycobacterium tuberculosis, with 1 case not having received examination.

CONCLUSIONS

Combining acid-fast staining and molecular pathological testing is helpful for accurately diagnosing placental TB.

Perinatal tuberculosis-An approach to an under-recognized diagnosis

Tuberculosis (TB) in young infants (<3 months of age), often referred to as perinatal TB, is underdiagnosed, leading to severe morbidity and high mortality. Perinatal TB includes both congenital and postnatal transmission of Mycobacterium tuberculosis. We aimed to increase an awareness of TB in neonates and young infants and to provide guidance on the assessment and management when in contact with mothers with TB during or soon after pregnancy. Approximately 217,000 pregnant women develop TB annually; if they are not diagnosed and treated during pregnancy, their infants are at high risk of adverse birth outcomes and TB disease. Although safe and effective antituberculosis treatment regimens are available during pregnancy, the diagnosis of TB is challenging. Infants born to mothers newly diagnosed with TB, not receiving any effective treatment or with cultures not yet negative, should be assessed for TB disease or M. tuberculosis infection. TB preventive therapy should be instituted if the infant is clinically well but exposed to TB, while prompt initiation of TB treatment is essential if TB disease is presumed. HIV status of mother and infant should be considered as this will affect the management. Further research is needed for the diagnosis and prevention of TB during pregnancy, an early diagnosis of TB in infants, and antituberculosis drug pharmacokinetics in young infants.

Tuberculosis infection and stillbirth in Ethiopia—A prospective cohort study

Background

Tuberculosis is among the leading causes of death among infectious diseases. Regions with a high incidence of tuberculosis, such as sub-Saharan Africa, are disproportionately burdened by stillbirth and other pregnancy complications. Active tuberculosis increases the risk of pregnancy complications, but the association between latent tuberculosis infection (LTBI) and pregnancy outcomes is unknown. We explored the effect of latent tuberculosis infection on the risk of stillbirth in women attending antenatal care clinics in Ethiopia, a country with >170 000 annual cases of active tuberculosis.

Method

Pregnant women were enrolled from antenatal care at three health facilities in Adama, Ethiopia, during 2015–2018, with assessment for previous and current active tuberculosis and testing for LTBI using QuantiFERON-TB-GOLD-PLUS. Proportions of stillbirth (≥ 20 weeks of gestation) and neonatal death (< 29 days of birth) were compared with respect to categories of maternal tuberculosis infection (tuberculosis-uninfected, LTBI, previous-, and current active tuberculosis). Multivariable logistic regression was performed for stillbirth.

Results

Among 1463 participants enrolled, the median age was 25 years, 10.2% were HIV-positive, 34.6% were primigravidae, and the median gestational age at inclusion was 18 weeks. Four (0.3%) were diagnosed with active tuberculosis during pregnancy, 68 (4.6%) reported previous treatment for active tuberculosis, 470 (32.1%) had LTBI, and 921 (63.0%) were tuberculosis-uninfected. Stillbirth was more frequent in participants with LTBI compared to tuberculosis-uninfected participants, although not reaching statistical significance (19/470, 4.0% vs 25/921, 2.7%, adjusted [for age, gravidity and HIV serostatus] odds ratio 1.38, 95% confidence interval 0.73–2.57, p = 0.30). Rates of neonatal death (5/470, 1.1% vs 10/921, 1.1%) were similar between these categories.

Conclusion

Latent tuberculosis infection was not significantly associated with stillbirth or neonatal death in this cohort. Studies based on larger cohorts and with details on causes of stillbirth, as well as other pregnancy outcomes, are needed to further investigate this issue.

Diagnosing Common Deadly Infections in the Era of COVID-19: A Case Report

The COVID-19 pandemic has challenged clinicians to recognize COVID-19 as one of the diagnostic explanation for common presentations, including fever, cough, and shortness of breath. Latent tuberculosis is responsible for 80% of active tuberculosis cases in the United States, and presentation can vary from asymptomatic to disseminated disease. This potential diagnosis should be thoroughly investigated in foreign-born patients in US hospitals, regardless of travel history and presenting symptoms. We report a patient diagnosed with postpartum disseminated tuberculosis with hematogenous spread to the fetus.

Application of loop-mediated isothermal amplification and next-generation sequencing in the diagnosis of maternal tuberculosis with multiple negative tests: A case report

RATIONALE

Tuberculosis (TB) is one of the top 10 causes of death worldwide and is the leading infectious cause of death. The incidence of TB, especially active TB, is increased in pregnant and postpartum women. Newborns can be infected with TB from their mothers through several routes. Diagnosis of TB in pregnant women and infants is difficult. Here, we report the simultaneous postdelivery diagnosis of TB in a mother and infant pair.

PATIENT CONCERNS

A 28-year-old woman presented with a sudden onset of convulsions, loss of consciousness, coughing, fever, and breathing difficulty. Her 18-day-old infant daughter developed cough and wheezing.

DIAGNOSIS

The mother's chest computed tomography showed diffuse interstitial changes and both lungs' exudation. Enhanced cranial magnetic resonance imaging showed scattered nodular intracranial lesions. A tuberculin skin test and an interferon-gamma release assay were negative. Xpert MTB/RIF (Xpert) testing and acid-fast bacilli smear of bronchoalveolar lavage (BAL) fluid of the mother were negative. Loop-mediated isothermal amplification of BAL fluid was positive for Mycobacterium tuberculosis, and next-generation sequencing confirmed the diagnosis of TB. A biopsy specimen also showed characteristic TB findings. The mother was diagnosed with TB and TB encephalitis. The infant's BAL fluid was positive for acid-fast bacilli and Xpert and, therefore, was diagnosed with TB.

INTERVENTIONS

The mother was treated with rifampicin and isoniazid for 9 months, ethambutol and pyrazinamide for 3 months, and prednisolone acetate for 8 weeks. The infant received ventilator-assisted ventilation for 10 days and anti-tuberculous therapy for 11 months.

OUTCOMES

After anti-tuberculous therapy, the mother and infant both gradually recovered. The mother's chest computed tomography showed significant recovery 9 months after discharge. The infant developed normally during the 11-month follow-up.

LESSONS

This mother-child case pair highlights the value of loop-mediated isothermal amplification and next-generation sequencing as new diagnostic technologies for diagnosing TB in patients with multiple negative tests.

HIV, placental pathology and birth outcomes - a brief overview

The spectrum of placental pathology in human immunodeficiency virus (HIV) is vast. Features observed are not only limited to the effects of the virus itself but may include that of coinfections such as tuberculosis and syphilis. The presence of other comorbidities and changes as a result of antiretroviral therapy may further confound the histologic findings. There is a paucity of unbiased information of the effects of maternal HIV on the placenta and how these changes relate to birth outcomes. Antiretroviral therapy, now in widespread use, has altered the course of maternal HIV disease and it is unknown whether this has altered the pathophysiology of HIV on the placenta. HIV-associated placental findings that have been most well described include acute chorioamnionitis, low placental weight and maternal vascular malperfusion, with a tendency towards lower rates of chronic villitis.

Decidual Granulomata of Unclear Significance

Granulomatous inflammation is a histologic finding with a relatively wide variety of causes. In general, considerations include infectious etiologies, autoimmune conditions, or foreign body reactions. Granulomatous inflammation is uncommonly seen in the placenta. We present a unique case of a young woman with preterm labor and rupture of membranes whose placenta demonstrated perivascular decidual granulomata in the membranes and the basal plate.

Intrauterine Tuberculosis Manifesting as Acute Chorioamnionitis: A Case Report and Review of the Literature

Congenital tuberculosis involving the placenta is an infrequent diagnosis, and the typical features of tuberculous placentitis involve a granulomatous reaction, reflecting a delayed hypersensitivity immune response in the host. However, the first reaction of the placenta to organisms hematogenously transmitted from the maternal circulation typically involves the innate immune response, manifesting as an acute neutrophilic villitis or intervillositis or both. This acute pattern of response to mycobacteria has only been documented rarely. We present a case of acute mycobacterial infection occurring in a preterm female with 28-weeks gestation, who was delivered by cesarean section because of fetal distress and who was subsequently confirmed to have congenital tuberculosis. The placenta showed an acute chorioamnionitis associated with acid-fast bacilli consistent with Mycobacteria tuberculosis. The mother was found to have a necrotizing granulomatous deciduitis, and that was postulated to have resulted in the direct spread of mycobacteria to the amniotic cavity. Thus, our case extends the acute placental response to mycobacteria to include chorioamnionitis. Although extremely rare, mycobacteria should be considered in the differential diagnosis of infectious agents causing acute chorioamnionitis, especially in geographic areas where tuberculosis is more prevalent.

Chronic villitis of unknown etiology and massive chronic intervillositis have similar immune cell composition

INTRODUCTION

Chronic villitis of unknown etiology (CVUE) and massive chronic intervillositis (MCI) are placental lesions associated with infiltration of mononuclear cells in the chorionic villi and the intervillous spaces, respectively. It is not well known whether immune cells in CVUE and MCI have similar phenotypic characteristics.

METHODS

A cross-sectional study of third trimester placentas was conducted to identify immune cell subpopulations in CVUE and MCI (n = 17/group). CVUE was diagnosed with H&E staining and antibody to CD3 in serial sections; and MCI, by the presence of massive infiltration of mononuclear cells in the intervillous spaces. Immune cells, ICAM-1 expression and nuclear factor κB (NF-κB) activation were determined immunohistochemically.

RESULTS

CVUE and MCI showed similar infiltrates, mainly CD68+ and CD3+ cells. Most cells (>80%) were CD45RB+, and one third were CD45RO+ in both lesions. There were slightly more CD8+ than CD4+ cells in both CVUE and MCI. More than 90% of cells in CVUE and MCI were ICAM-1+ with NFκB nuclear localization. Syncytiotrophoblast ICAM-1 expression was significantly (p < 0.001) higher in MCI (mean of 81.0; range of 71.6-86.0) than in CVUE (52.4; 36.4-59.4) or normal placentas (0.2; 0.0-0.6). Both, failure of physiologic transformation of spiral arteries and placental atherosclerosis-like lesions of atherosis were significantly more frequent in MCI than in CVUE or normal placentas (p = 0.044 and p = 0.007, respectively).

DISCUSSION

These finding suggest that MCI and CVUE have very similar infiltration of immune cells although MCI has more severe placental lesions.

High latency of tuberculosis manifestation in a premature extremely low birth weight infant with favorable outcome

We report a case of possible congenital tuberculosis in a 22+2 weeks, 460 g, vaginally delivered female infant born to a mother suffering from tuberculous endometritis, diagnosed soon after delivery. At 156 days of age, Mycobacterium tuberculosis was detected via PCR from the infant's gastric juice and was subsequently isolated. There was no evidence for horizontal transmission. Mother and child were treated successfully. This case illustrates the possibility of significant latency between infection and clinical manifestation in preterm infants and also emphasizes the need for urgent treatment of neonates in such situations.

Villitis of Unknown Etiology and Massive Chronic Intervillositis

Villitis of unknown etiology (VUE) is a common lesion affecting from 6.6% to 33.8% of third-trimester placentas. VUE needs to be distinguished from villitis of infectious etiology, most commonly cytomegalovirus and syphilis. Clinically, this lesion is associated with intrauterine growth retardation, intrauterine fetal demise, fetal neural impairment, maternal alloimmune and autoimmune disease, and maternal hypertension. It has a tendency to recur in subsequent pregnancies. Massive chronic intervillositis (MCI), also known as chronic histiocytic intervillositis, is a rare lesion that has an unclear relationship with VUE. MCI is associated with recurrent abortions.

Ascending Infection: Acute Chorioamnionitis

Acute chorioamnionitis is a major cause of spontaneous preterm birth, accounting for more than 40% of deliveries complicated by preterm premature rupture of membranes or preterm labor. In the majority of cases, especially in preterm births, acute chorioamnionitis is caused by ascending polymicrobial infection. Recent evidence suggests that in some cases acute chorioamnionitis may have a noninfectious cause. In addition to the nonspecific patterns of conventional acute chorioamnionitis, this article describes characteristic inflammatory patterns indicative of a specific infectious cause. Several inflammatory entities of putative immunologic (noninfectious) etiology are addressed, including eosinophilic/T-cell vasculitis and chronic chorioamnionitis.