Unique alterations in infection-induced immune activation during pregnancy.

BACKGROUND: Immune responses to infection are uniquely regulated during gestation to allow for antimicrobial defence and tissue repair, whilst preventing damage to developing fetal organs or the triggering of preterm labour. OBJECTIVE: A review and analysis of studies delineating gestation-specific immune modulation and intra-amniotic regulation of pro-inflammatory immunity. SEARCH STRATEGY: Identification of the alterations between the fetus/neonate and adult with regard to the endogenous and infection-induced expression of molecules with immune regulatory properties, and the characterisation of intra-amniotic immune mediators that inhibit bacterial-induced pro-inflammatory cytokine production. SELECTION CRITERIA: English and non-English publications from 1985 to the present. DATA COLLECTION AND ANALYSIS: An electronic literature search using MEDLINE, PubMed, articles cited in the primary sources, as well as pregnancy-related immunology research from our laboratory at Weill Medical College of Cornell University. MAIN RESULTS: During fetal development, interleukin (IL)-23, IL-10 and IL-6, as well as T-helper-17 (Th17)-mediated immune responses, are upregulated, whereas tumour necrosis factor-α (TNF-α) and IL-1ß- and Th1-mediated immune responses are downregulated in the intrauterine environment (both the fetal compartment and the amniotic compartment). Infection-related immunity during gestation is preferentially directed towards combating extracellular microbial pathogens. Amniotic fluid and the neonatal circulation contain multiple components that improve the ability of the developing neonate to tolerate microbial-induced immune activation. CONCLUSIONS: The repertoire of immune mechanisms to control infection and inflammation differ between fetal and adult life. The dual mechanisms of resistance to infection and tolerance to infection-induced immune activation prevent damage to the developing fetus and the triggering of premature labour.

Intrauterine sling: a complication of the stuck twin syndrome.

Stuck twin syndrome usually presents with polyhydramnios in the recipient sac and severe oligohydramnios in the donor sac. The donor is displaced against the uterine wall and remains adherent in that position. We present a case in which the diagnosis was more complicated, owing to the suspension of the stuck twin by a sling within the sac of the recipient. A monochorionic diamnionic twin gestation was complicated by twin-twin transfusion syndrome at 18 weeks of gestation. In our example, the stuck twin was suspended by a sling from the placenta. The sling band represented the intertwin membrane that was folded upon itself. Amniotic fluid from the recipient twin was present in three dimensions around the stuck twin, except for the sling band. The suspension of the stuck twin by a sling within the amniotic fluid of the recipient is an unusual manifestation of the stuck twin syndrome.

BRa (HPA-5b) incompatibility may cause thrombocytopenia in neonates of mothers with immune thrombocytopenic purpura.

PURPOSE: The association of anti-Br(a) immunoglobulin G (IgG) platelet alloantibodies with the development of thrombocytopenia in neonates of mothers with autoimmune thrombocytopenic purpura (ITP) is reported. METHODS: Between March 1994 and July 1997, 28 consecutive pregnant women with ITP seen at New York Hospital were screened for platelet-reactive antiglycoprotein (glycoprotein [GP] IIb/IIIa, Ib/IX, and Ia/IIa) antibodies. RESULTS: The sera from 6 of these 28 women contained IgG alloantibodies to GP Ia/IIa directed against the Br(a) (HPA-5b) antigen. Only three families each had at least one Br(a)+ and at least one Br(a)- infant. Platelet typing in these families revealed that the mothers were Br(b/b) (Br(a)-) and the fathers were Br(a/b) (Br(a)+). Platelet counts < 100,000/microl occurred only in 2 of the 3 infants who were Br(a)+. The platelet counts were significantly lower in the three Bra+ infants compared to the five Br(a)- infants (p = 0.038). CONCLUSION: Platelet alloimmunization with anti-Br(a) can cause neonatal thrombocytopenia in infants of mothers with ITP. Platelet antibody testing in the pregnant women with ITP is recommended.

Vascularity of uterine myomas: assessment by color and pulsed Doppler ultrasound.

OBJECTIVE: To evaluate the effects of different clinical and anatomical factors on the vascularity of uterine myomas METHODS: The study group included 195 patients, 153 premenopausal and 42 postmenopausal. Four hundred five myomas, 316 in the first group and 89 in the second, were studied by color Doppler ultrasound. Differences in the visualization of blood flow and resistance index (RI) were analyzed according to several factors, including: menopausal status, phase of menstrual cycle, duration of menopause, size and location of the myomas, and secondary changes within the myomas. RESULTS: The size of myomas was the most important single factor in determining both visualization of blood flow and RI. A higher blood flow visualization rate (BFVR) and a lower RI were found: (1) in the premenopausal compared with the postmenopausal patients (P < 0.05), (2) in the group of larger myomas compared with the group of smaller myomas (P < 0.0001), and (3) in submucosal and subserosal myomas compared with intramural myomas (P < 0.05). Other above-mentioned factors did have some, but not significant, influence on the visualization of blood flow and resistance to blood flow. CONCLUSION: Differences in the vascularity and resistance to blood flow in uterine myomas may limit the clinical use of color Doppler ultrasound.

Fetal transfusion therapy.

Rapid advances are occurring in the diagnosis and treatment of the fetus with a red blood cell or platelet cytopenia. Noninvasive methods of monitoring the alloimmunized pregnancy, invasive methods such as amniocentesis and cordocentesis, and intrauterine transfusion therapy of both red cells and platelets, are being further refined to allow the prompt recognition and treatment of fetal cytopenias. Specialized centers have now accrued a large experience in the management of the fetus severely affected by alloimmunization. Advances in ultrasound, blood banking techniques, and genetic engineering technology have spurred the most recent advances. The indications for diagnosis, timing and frequency of invasive procedures for treatment, and technical considerations regarding preparation of blood products and volume of transfusion, are outlined in this review. Polymerase chain reaction (PCR) determination of fetal Rh(D) genotype by chorionic villus sampling or amniocentesis in the first or second trimesters is a recent clinically useful advance. The advent of hematopoietic stem cell transplantation and the potential for gene therapy are exciting advances in the treatment and prevention of hematopoietic diseases, including, but not limited, to the fetal cytopenias.

Rapid exclusion of chromosomal aneuploidies by fluorescence in situ hybridization prior to fetal surgery for obstructive uropathy--a case report.

Ultrasound of a fetus at 17 weeks gestation revealed posterior urethral valve syndrome with anhydramnios. Fluorescence in situ hybridization (FISH) to detect aneuploidies of chromosomes 13, 18, 21, X and Y was performed on transitional cells from the fetal bladder obtained at percutaneous vesicocentesis, followed by conventional cytogenetics. Fetal urine was chosen due to unavailability of amniotic fluid for karyotypic analysis. A nonlethal (disomic) karyotype was suggested by FISH, and thus placement of a vesicoamniotic shunt was performed. The ability to prognosticate in cases of obstructive uropathy is not absolute, and fetal surgery for relief of urinary obstruction is best performed at the earliest possible gestational age. Thus, all available means for rapidly ruling out lethal congenital anomalies should be undertaken in cases of obstructive uropathy prior to any decision regarding fetal surgery.