Syphilis
Syphilis is a sexually transmitted bacterial infection. It is caused by Treponema pallidum, a spiral-shaped bacterium. It can affect both men and women who are sexually active. Syphilis can be transmitted from an infected person to another during oral, anal and vaginal sex and oral-genital contact. It can also be passed on by direct skin contact with someone who has syphilis sores or a syphilis rash and by sharing sex toys. Syphilis can also be transmitted by blood transfusion. Those who have tested positive for syphilis are vulnerable to other STDs like Gonorrhea and HIV.
Syphilis develops in stages. Not everyone will go through all the stages. Between the stages are periods that are symptom-free or latent periods. When the infection is active, symptoms are noticeable. When it’s not active, the symptoms are unnoticeable but syphilis persists.
Primary syphilis: Syphilis is highly contagious during the first stage. The incubation period is around 21 days before the first signs and symptoms appear. A painless red sore called a chancre appears on the part of the body like vagina, rectum, penis or mouth, places where the spirochetes moved from the infected person to another. The painless sore isn’t noticed or recognized most of the time and the infected individual may not fall ill. The chancre may heal after 4 to 6 weeks but it does not indicate that syphilis has actually gone away. It continues to spread throughout the body.
Secondary syphilis: The bacterial has spread into the bloodstream. Without treatment, blood-borne spread of Treponema pallidum over the next several weeks to months results in secondary syphilis. It usually occurs 2 to 8 weeks after the appearance of chancre sore and several weeks after chancre have healed. Symptoms include fever, multiform skin eruptions, iritis, alopecia, mucous patches and severe pain in the head and joints. The signs and symptoms of secondary syphilis will resolve with or without treatment, but without treatment, the infection will progress to the latent stage of disease.
Latent (hidden) syphilis: The signs of the disease may go away, but the disease is present in the body. Syphilis can remain latent for many years.
Tertiary syphilis: Also termed as late-stage syphilis, tertiary syphilis may occur many years after the original infection. The infection has already spread all over the body and can affect the brain, heart, spinal cord and bones. Symptoms vary depending on which organ is infected and affected.
Congenital syphilis: A pregnant syphilis infected woman may pass on the infection through the placenta to the child during fetal development or delivery which is referred to as congenital syphilis. If the infected pregnant woman is not treated before 18th week of pregnancy, the child is most likely to be affected with congenital syphilis. Some babies with congenital syphilis have no symptoms at birth but develop them in a few weeks if not treated immediately. As a precautionary measure, syphilis screening tests (VDRL, RPR, FTA-ABS) has been made a routine part of prenatal care during pregnancy.
Chorionic Villus Sampling
The diagnostic procedure of taking out a sample tissue (Choroinic Villi) from the placenta to detect congenital abnormalities in a fetus is known as Chorionic Villus Sampling (CVS). With the guidance of ultrasound, the position of placenta is first determined. There are two methods - trans-cervical and trans-abdominal to perform this test. The position of the placenta helps the physician choose a suitable method. For trans-cervical CVS, parameters like the position of the uterus, the size of the gestational sac and the position of the placenta inside the uterus are first determined using abdominal ultrasound. Using a good antiseptic, the vulva, vagina and the cervix are cleansed. The abdomen is also cleansed for trans-abdominal procedure.
Trans cervical procedure: A thin plastic tube is inserted through the vagina and cervix for the trans-cervical procedure to reach the placenta. A tiny sample of chorionic villus tissue is taken out after locating the exact position of the placenta.
Trans-abdominal procedure: This procedure is similar to the earlier one, but a needle is inserted through the abdomen in this test to reach the uterus and then to the placenta. The chorionic villus sample tissue is drawn into the syringe, while the needle is guided by ultrasound.
This sample is then taken to the laboratory for evaluation. This procedure can be conducted even earlier than amniocentesis to detect any congenital defects present in the fetus. It is done at around 10 to 12 weeks after the last menstruation. Study of the DNA, chromosomes and enzymes of the fetus can be conducted using the sample taken out during the test. Results are available within a week or two. If there are any abnormalities found in the fetus, it is easy to conduct a therapeutic abortion, in case it is necessary. Pregnant women over the age of 35 who are at risk for giving birth to a baby with Downs Syndrome or those who have had birth defects in an earlier pregnancy are advised this test. For detecting neural tube defects and the Rh-incompatibility, amniocentesis is a better option. Hemoglobinopathies and Tay-Sachs disease can be detected through Chorionic Villus Sampling.
The risk involved in using CVS is slightly higher when compared to amniocentesis. Some complications like rupture of the amniotic membrane, miscarriage, infection, bleeding, Rh-incompatibility in the mother if she is Rh-negative and contamination of the sample with maternal cells can occur. When CVS is performed after 10 weeks of gestational period, there is a risk for limb defects in the fetus. If the mother's blood is Rh-negative, she has to receive RhoGAM to avoid Rh incompatibility. After the CVS, it is advised to have an ultrasound done after about two or four days to ensure the fetus is fine.
Night blindness
Night blindness or Nyctalopia is inability or difficulty in seeing in the night or poor light. While it is congenital in some, in others it is caused due to injury, certain drugs or other causes. This causes problems especially during driving at night. Hemeralopia is the opposite of night blindness where a person is unable to see in bright light. But this condition is more rare. Persons suffering from night blindness tend to notice reduced contrast vision; as their eyes take more time to adjust from brightly lit areas to dim ones. Some causes for night blindness are cataract and nearsightedness. An ophthalmologist might conduct tests such as retinal exam, color vision testing and pupil light reflex.
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