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The Centers for Disease Control and Prevention (CDC) recommends HIV testing for all pregnant women as a part of routine prenatal care. The test is usually performed in the first trimester of pregnancy with other routine laboratory tests. HIV testing is recommended because HIV-infected women who do not receive testing are more likely to transmit the infection to their children.
HIV testing may be offered to pregnant women on an "opt-in" or an "opt-out" basis. In the "opt-in" model, women are counseled on HIV testing and elect to receive the test by signing a consent form. In the "opt-out" model, the HIV test is automatically performed with other routine prenatal tests. If a woman does not want to be tested for HIV, she must specifically refuse the test and sign a form declining testing. The CDC recommends "opt-out" testing for all pregnant women because it improves disease detection and treatment and helps reduce transmission to children.
If a woman chooses to decline testing, she will not receive the test. However, she will continue to receive HIV counseling throughout the pregnancy so that she may be as informed as possible about the disease and its impact. She will be offered HIV testing at all stages of her pregnancy in case she changes her mind.
HIV testing begins with a screening test. The most common screening test is the rapid HIV antibody test which tests for HIV antibodies in blood, urine, or oral fluid. HIV antibodies are only produced if an individual is infected with the disease. Therefore, presence of the antibodies is indicative of an HIV infection. Sometimes, however, a person may be infected with HIV but the body has not produced enough antibodies to be detected by the test. If a woman has risk factors for HIV infection but tests negative on the initial screening test, she should be retested in 3 months to confirm that she does not have HIV. Another screening test that is more specific is the HIV antigen/antibody test. This is a newer blood test that can detect HIV infection quicker than the antibody test because it detects both virus particles and antibodies in the blood.
Any woman who has a positive HIV screening test must receive follow-up testing to confirm the diagnosis. The follow-up test can differentiate HIV-1 from HIV-2 and is a more specific antibody test. It may also detect the virus directly in the bloodstream.
Babies born to HIV-positive women should receive a 6-week course of zidovudine (AZT). The medication should be started within the first 6 to 12 hours of life. The baby should be tested for HIV at 14 to 21 days of life, at 1 to 2 months of age, and once more at 4 to 6 months of age. Usual antibody based testing is unreliable in infants due to the transmission of maternal antibodies. A qualitative HIV DNA PCR assay is recommended as it will detect pro-viral HIV DNA since HIV RNA may be suppressed by ART. In order to ensure the baby is HIV-negative, there must be two negative test results. Since zidovudine has been known to cause or worsen anemia, the baby's blood count should be routinely checked during AZT therapy.
To reduce the risk of developing "Pneumocystis jirovecii" pneumonia (PCP), all infants born to HIV-positive mothers should receive trimethoprim/sulfamethoxazole at age 4–6 weeks.
Although the risk is very low, HIV can also be transmitted to a baby through food that was previously chewed (pre-chewed) by a mother or caretaker infected with HIV. To be safe, babies should not be fed pre-chewed food.
The important factors for successful prevention of GBS-EOD using IAP and the universal screening approach are:
- Reach most pregnant women for antenatal screens
- Proper sample collection
- Using an appropriate procedure for detecting GBS
- Administering a correct IAP to GBS carriers
Most cases of GBS-EOD occur in term infants born to mothers who screened negative for GBS colonization and in preterm infants born to mothers who were not screened, though some false-negative results observed in the GBS screening tests can be due to the test limitations and to the acquisition of GBS between the time of screening and delivery. These data show that improvements in specimen collection and processing methods for detecting GBS are still necessary in some settings. False-negative screening test, along with failure to receive IAP in women delivering preterm with unknown GBS colonization status, and the administration of inappropriate IAP agents to penicillin-allergic women account for most missed opportunities for prevention of cases of GBS-EOD.
GBS-EOD infections presented in infants whose mothers had been screened as GBS culture-negative are particularly worrying, and may be caused by incorrect sample collection, delay in processing the samples, incorrect laboratory techniques, recent antibiotic use, or GBS colonization after the screening was carried out.
Neonatal sepsis of the newborn is an infection that has spread through the entire body. The inflammatory response to this systematic infection can be as serious as the infection itself. In infants that weigh under 1500 g, sepsis is the most common cause of death. Three to four percent of infants per 1000 births contract sepsis. The mortality rate from sepsis is near 25%. Infected sepsis in an infant can be identified by culturing the blood and spinal fluid and if suspected, intravenous antibiotics are usually started. Lumbar puncture is controversial because in some cases it has found not to be necessary while concurrently, without it estimates of missing up to one third of infants with meningitis is predicted.
No current culture-based test is both accurate enough and fast enough to be recommended for detecting GBS once labour starts. Plating of swab samples requires time for the bacteria to grow, meaning that this is unsuitable as an intrapartum point-of-care test.
Alternative methods to detect GBS in clinical samples (as vaginorectal swabs) rapidly have been developed, such are the methods based on nucleic acid amplification tests, such as polymerase chain reaction (PCR) tests, and DNA hybridization probes. These tests can also be used to detect GBS directly from broth media, after the enrichment step, avoiding the subculture of the incubated enrichment broth to an appropriate agar plate.
Testing women for GBS colonization using vaginal or rectal swabs at 35–37 weeks of gestation and culturing them in enriched media is not as rapid as a PCR test that would check whether the pregnant woman is carrying GBS at delivery. And PCR tests, allow starting IAP on admission to the labour ward in those women in whom it is not known if they are GBS carriers or not. PCR testing for GBS carriage could, in the future, be sufficiently accurate to guide IAP. However, the PCR technology to detect GBS must be improved and simplified to make the method cost-effective and fully useful as point-of-care testing]] to be carried out in the labour ward (bedside testing). These tests still cannot replace antenatal culture for the accurate detection of GBS carriers.
People infected with CMV develop antibodies to it, initially IgM later IgG indicating current infection and immunity respectively. If the virus is detected in the blood, saliva, urine or other body tissues, it means that the person has an active infection.
When infected with CMV, most women have no symptoms, but some may have symptoms resembling mononucleosis. Women who develop a mononucleosis-like illness during pregnancy should consult their medical provider.
The Centers for Disease Control and Prevention (CDC) does not recommend routine maternal screening for CMV infection during pregnancy because there is no test that can definitively rule out primary CMV infection during pregnancy. Women who are concerned about CMV infection during pregnancy should practice CMV prevention measures.Considering that the CMV virus is present in saliva, urine, tears, blood, mucus, and other bodily fluids, frequent hand washing with soap and water is important after contact with diapers or oral secretions, especially with a child who is in daycare or interacting with other young children on a regular basis.
A diagnosis of congenital CMV infection can be made if the virus is found in an infant's urine, saliva, blood, or other body tissues during the first week after birth. Antibody tests cannot be used to diagnose congenital CMV; a diagnosis can only be made if the virus is detected during the first week of life. Congenital CMV cannot be diagnosed if the infant is tested more than one week after birth.
Visually healthy infants are not routinely tested for CMV infection although only 10–20% will show signs of infection at birth though up to 80% may go onto show signs of prenatal infection in later life. If a pregnant woman finds out that she has become infected with CMV for the first time during her pregnancy, she should have her infant tested for CMV as soon as possible after birth.
Symptoms and the isolation of the virus pathogen the upper respiratory tract is diagnostic. Virus identification is specific immunologic methods and PCR. The presence of the virus can be rapidly confirmed by the detection of the virus antigen. The methods and materials used for identifying the RSV virus has a specificity and sensitivity approaching 85% to 95%. Not all studies confirm this sensitivity. Antigen detection has comparatively lower sensitivity rates that approach 65% to 75%.
When physical examination of the newborn shows signs of a vertically transmitted infection, the examiner may test blood, urine, and spinal fluid for evidence of the infections listed above. Diagnosis can be confirmed by culture of one of the specific pathogens or by increased levels of IgM against the pathogen.
Most healthy people working with infants and children face no special risk from CMV infection. However, for women of child-bearing age who previously have not been infected with CMV, there is a potential risk to the developing unborn child (the risk is described above in the Pregnancy section). Contact with children who are in day care, where CMV infection is commonly transmitted among young children (particularly toddlers), may be a source of exposure to CMV. Since CMV is transmitted through contact with infected body fluids, including urine and saliva, child care providers (meaning day care workers, special education teachers, as well as mothers) should be educated about the risks of CMV infection and the precautions they can take. Day care workers appear to be at a greater risk than hospital and other health care providers, and this may be due in part to the increased emphasis on personal hygiene in the health care setting.
Recommendations for individuals providing care for infants and children:
- Employees should be educated concerning CMV, its transmission, and hygienic practices, such as handwashing, which minimize the risk of infection.
- Susceptible nonpregnant women working with infants and children should not routinely be transferred to other work situations.
- Pregnant women working with infants and children should be informed of the risk of acquiring CMV infection and the possible effects on the unborn child.
- Routine laboratory testing for CMV antibody in female workers is not specifically recommended due to its high occurrence, but can be performed to determine their immune status.
Each type of vertically transmitted infection has a different prognosis. The stage of the pregnancy at the time of infection also can change the effect on the newborn.
Pregnant women are more severely affected by influenza, hepatitis E, herpes simplex and malaria. The evidence is more limited for coccidioidomycosis, measles, smallpox, and varicella. Pregnancy may also increase susceptibility for toxoplasmosis.
During the 2009 H1N1 pandemic, as well as during interpandemic periods, women in the third trimester of pregnancy were at increased risk for severe
disease, such as disease requiring admission to an intensive care unit or resulting in death, as compared with women in an earlier stage of pregnancy.
For hepatitis E, the case fatality rate among pregnant women has been estimated to be between 15% and 25%, as compared with a range of 0.5 to 4% in the population overall, with the highest susceptibility in the third trimester.
Primary herpes simplex infection, when occurring in pregnant women, has an increased risk of dissemination and hepatitis, an otherwise rare complication in immunocompetent adults, particularly during the third trimester. Also, recurrences of herpes genitalis increase in
frequency during pregnancy.
The risk of severe malaria by "Plasmodium falciparum" is three times as high in pregnant women, with a median maternal mortality of 40% reported in studies in the Asia–Pacific region. In women where the pregnancy is not the first, malaria infection is more often asymptomatic, even at high parasite loads, compared to women having their first pregnancy. There is a decreasing susceptibility to malaria with increasing parity, probably due to immunity to pregnancy-specific antigens. Young maternal age and increases the risk. Studies differ whether the risk is different in different . Limited data suggest that malaria caused by "Plasmodium vivax" is also more severe during pregnancy.
Severe and disseminated coccidioidomycosis has been reported the occur in increased frequency in pregnant women in several reports and case series, but subsequent large surveys, with the overall risk being rather low.
Varicella occurs at an increased rate during pregnancy, but mortality is not higher than that among men and non-pregnant women.
Listeriosis mostly occurs during the third trimester, with Hispanic women appearing to be at particular risk. Listeriosis is a vertically transmitted infection that may cause miscarriage, stillbirth, preterm birth, or serious neonatal disease.
Some infections are vertically transmissible, meaning that they can affect the child as well.
There are several potential risk factors or causes to this increased risk:
- An increased immune tolerance in pregnancy to prevent an immune reaction against the fetus
- Maternal physiological changes including a decrease in respiratory volumes and urinary stasis due to an enlarging uterus.
- The presence of a placenta for pathogens to use as a habitat, such as by "L. monocytogenes" and "P. falciparum".
Chorioamnionitis can be diagnosed from a histologic examination of the fetal membranes.
Infiltration of the chorionic plate by neutrophils is diagnostic of (mild) chorioamnionitis. More severe chorioamnionitis involves subamniotic tissue and may have fetal membrane necrosis and/or abscess formation.
Severe chorioamnionitis may be accompanied by vasculitis of the umbilical blood vessels (due to the fetus' inflammatory cells) and, if very severe, funisitis (inflammation of the umbilical cord's connective tissue).
In CNS infection cases, "L. monocytogenes" can often be cultured from the blood or from the CSF (Cerebrospinal fluid).
According to American Congress of Obstetricians and Gynecologists, the main methods to calculate gestational age are:
- Directly calculating the days since the beginning of the last menstrual period.
- Early obstetric ultrasound, comparing the size of an embryo or fetus to that of a reference group of pregnancies of known gestational age (such as calculated from last menstrual periods), and using the mean gestational age of other embryos or fetuses of the same size. If the gestational age as calculated from an early ultrasound is contradictory to the one calculated directly from the last menstrual period, it is still the one from the early ultrasound that is used for the rest of the pregnancy.
- In case of in vitro fertilization, calculating days since oocyte retrieval or co-incubation and adding 14 days.
Use of male condoms or female condoms may help prevent the spread of trichomoniasis, although careful studies have never been done that focus on how to prevent this infection. Infection with Trichomoniasis through water is unlikely because "Trichomonas vaginalis" dies in water after 45–60 minutes, in thermal water after 30 minutes to 3 hours and in d urine after 5–6 hours.
Currently there are no routine standard screening requirements for the general U.S. population receiving family planning or STI testing. The Centers for Disease Control and Prevention (CDC) recommends Trichomoniasis testing for females with vaginal discharge and can be considered for females at higher risk for infection or of HIV-positive serostatus.
The advent of new, highly specific and sensitive trichomoniasis tests present opportunities for new screening protocols for both men and women. Careful planning, discussion, and research are required to determine the cost-efficiency and most beneficial use of these new tests for the diagnosis and treatment of trichomoniasis in the U.S., which can lead to better prevention efforts.
A number of strategies have been found to improve follow-up for STI testing including email and text messaging as reminders of appointments.
Recommendations for the diagnosis of congenital toxoplasmosis include: prenatal diagnosis based on testing of amniotic fluid and ultrasound examinations; neonatal diagnosis based on molecular testing of placenta and cord blood and comparative mother-child serologic tests and a clinical examination at birth; and early childhood diagnosis based on neurologic and ophthalmologic examinations and a serologic survey during the first year of life. During pregnancy, serological testing is recommended at three week intervals.
Even though diagnosis of toxoplasmosis heavily relies on serological detection of specific anti-"Toxoplasma" immunoglobulin, serological testing has limitations. For example, it may fail to detect the active phase of "T. gondii" infection because the specific anti-"Toxoplasma" IgG or IgM may not be produced until after several weeks of infection. As a result, a pregnant woman might test negative during the active phase of "T. gondii" infection leading to undetected and therefore untreated congenital toxoplasmosis. Also, the test may not detect "T. gondii" infections in immunocompromised patients because the titers of specific anti-"Toxoplasma" IgG or IgM may not rise in this type of patient.
Many PCR-based techniques have been developed to diagnose toxoplasmosis using clinical specimens that include amniotic fluid, blood, cerebrospinal fluid, and tissue biopsy. The most sensitive PCR-based technique is nested PCR, followed by hybridization of PCR products. The major downside to these techniques is that they are time consuming and do not provide quantitative data.
Real-time PCR is useful in pathogen detection, gene expression and regulation, and allelic discrimination. This PCR technique utilizes the 5' nuclease activity of "Taq" DNA polymerase to cleave a nonextendible, fluorescence-labeled hybridization probe during the extension phase of PCR. A second fluorescent dye, e.g., 6-carboxy-tetramethyl-rhodamine, quenches the fluorescence of the intact probe. The nuclease cleavage of the hybridization probe during the PCR releases the effect of quenching resulting in an increase of fluorescence proportional to the amount of PCR product, which can be monitored by a sequence detector.
Toxoplasmosis cannot be detected with immunostaining. Lymph nodes affected by "Toxoplasma" have characteristic changes, including poorly demarcated reactive germinal centers, clusters of monocytoid B cells, and scattered epithelioid histiocytes.
The classic triad of congenital toxoplasmosis includes: chorioretinitis, hydrocephalus, and intracranial artheriosclerosis.
The management of PROM remains controversial, and depends largely on the gestational age of the fetus and other complicating factors. The risks of quick delivery (induction of labor) vs. watchful waiting in each case is carefully considered before deciding on a course of action.
As of 2012, the Royal College of Obstetricians and Gynaecologists advised, based on expert opinion and not clinical evidence, that attempted delivery during maternal instability, increases the rates of both fetal death and maternal death, unless the source of instability is an intrauterine infection.
In all women with PROM, the age of the fetus, its position in the uterus, and its wellbeing should be evaluated. This can be done with ultrasound, electronic fetal heart rate monitoring, and uterine activity monitoring. This will also show whether or not uterine contractions are happening which may be a sign that labor is starting. Signs and symptoms of infection should be closely monitored, and, if not already done, a group B streptococcus (GBS) culture should be collected.
At any age, if the fetal well-being appears to be compromised, or if intrauterine infection is suspected, the baby should be delivered quickly by artificially stimulating labor (induction of labor).
Obstetric ultrasonography can detect fetal abnormalities, detect multiple pregnancies, and improve gestational dating at 24 weeks. The resultant estimated gestational age and due date of the fetus are slightly more accurate than methods based on last menstrual period. Ultrasound is used to measure the nuchal fold in order to screen for Downs syndrome.
For sexually active women who are not pregnant, screening is recommended in those under 25 and others at risk of infection. Risk factors include a history of chlamydial or other sexually transmitted infection, new or multiple sexual partners, and inconsistent condom use. For pregnant women, guidelines vary: screening women with age or other risk factors is recommended by the U.S. Preventive Services Task Force (USPSTF) (which recommends screening women under 25) and the American Academy of Family Physicians (which recommends screening women aged 25 or younger). The American College of Obstetricians and Gynecologists recommends screening all at risk, while the Centers for Disease Control and Prevention recommend universal screening of pregnant women. The USPSTF acknowledges that in some communities there may be other risk factors for infection, such as ethnicity. Evidence-based recommendations for screening initiation, intervals and termination are currently not possible. For men, the USPSTF concludes evidence is currently insufficient to determine if regular screening of men for chlamydia is beneficial. They recommend regular screening of men who are at increased risk for HIV or syphilis infection.
In the United Kingdom the National Health Service (NHS) aims to:
1. Prevent and control chlamydia infection through early detection and treatment of asymptomatic infection;
2. Reduce onward transmission to sexual partners;
3. Prevent the consequences of untreated infection;
4. Test at least 25 percent of the sexually active under 25 population annually.
5. Retest after treatment.
Globally, an estimated 125 million or more pregnant women per year risk contracting PAM. Pregnancy-related malaria causes around 100,000 infant deaths each year, due in large part to low birth weight.
There are three main ways to test for Trichomoniasis.
- The first is known as saline microscopy. This is the most commonly used method and requires an endocervical, vaginal, or penile swab specimen for examination under a microscope. The presence of one or multiple trichomonads constitutes a positive result. This method is cheap but has a low sensitivity (60-70%) often due to an inadequate sample, resulting in false negatives.
- The second diagnostic method is culture, which has historically been the "gold standard" in infectious disease diagnosis. Trichomonas Vaginalis culture tests are relatively cheap; however, sensitivity is still somewhat low (70-89%).
- The third method includes the nucleic acid amplification tests (NAATs) which are more sensitive. These tests are more costly than microscopy and culture, and are highly sensitive (80-90%).
Chorioamnionitis is a risk factor for periventricular leukomalacia and cerebral palsy.
Amniocentesis and chorionic villus sampling are procedures conducted to assess the fetus. A sample of amniotic fluid is obtained by the insertion of a needle through the abdomen and into the uterus. Chorionic villus sampling is a similar procedure with a sample of tissue removed rather than fluid. These procedures are not associated with pregnancy loss during the second trimester but they are associated with miscarriages and birth defects in the first trimester. Miscarriage caused by invasive prenatal diagnosis (chorionic villus sampling (CVS) and amniocentesis) is rare (about 1%).
A review article in The New England Journal of Medicine based on a consensus meeting of the Society of Radiologists in Ultrasound in America (SRU) has suggested that miscarriage should be diagnosed only if any of the following criteria are met upon ultrasonography visualization: