TORCH Profile – Part 3 – Herpes simplex (Herpesvirus type 1 and type 2)

The sample for the TORCH profile

1. The venous blood is collected to prepare the serum.
2. The other sample used is blood, urine, and spinal fluid for evidence of the infections for TORCH.
3. Diagnosis can be confirmed by the culture of one of the specific pathogens or by increased levels of IgM against the specific pathogen.

Purpose of the test (Indications):

1. TORCH profile is done to find the cause of premature birth or abortion.
2. TORCH is used to screen infants for infections such as toxoplasmosis, cytomegalovirus, herpes simplex, rubella, and syphilis.

Pathophysiology of TORCH

1. TORCH profile includes the following tests :
   1. Toxoplasmosis antibody.
   2. Rubella antibody.
   3. Herpes Simplex.
   4. Cytomegalovirus
   5. some people include syphilis as well.
2. These infections may lead to birth defects, growth delay, brain, and nervous system problems in the baby.
3. If TORCH screening on infants is positive, more testing will be needed to confirm the diagnosis. The mother will also need to be checked.
4. The test is ordered when a pregnant woman is suspected of having any of the TORCH infections.
5. These infections can be serious if they occur during pregnancy because they can cross the placenta from the mother to the developing fetus and can cause congenital defects in the newborn.
6. The TORCH infections cause a syndrome characterized by:
   1. Microcephaly.
   2. Sensorineural deafness.
   3. Chorioretinitis.
   4. Hepatosplenomegaly.
   5. Thrombocytopenia.
7. TORCH infection sign/symptoms are:
   1. Fever and poor feeding.
   2. The newborn is often small for gestational age.
   3. A petechial rash on the skin may be present, with small reddish or purplish spots due to bleeding from capillaries under the skin.
   4. An enlarged liver and spleen (hepatosplenomegaly) are common, and jaundice.
   5. Hearing impairment, eye problems, mental retardation, autism, and death can be caused by TORCH infections.
   6. The mother often has a mild infection with few or no symptoms.
8. The examiner may test blood, urine, and spinal fluid for evidence of the infections for TORCH.
9. Diagnosis can be confirmed by the culture of one of the specific pathogens or by increased levels of IgM against the pathogen.

Herpes simplex (HS)

Sample

• A blood sample to prepare the serum is needed.

Pathology

1. There are five human herpesviruses:
   1. Herpes simplex 1.
   2. Herpes simplex 2.
   3. Varicella-zoster.
   4. Epstein- Barr virus.
   5. Cytomegalovirus.
2. Herpes simplex exists in two forms :
   1. HS type 1.
   2. HS type 2.
   3. Virtually all adult sera are positive for the Herpes antibodies to one of the types.
   4. Even antibody-positive individuals may get repeated attacks of infection. So antibodies are not a useful indicator of immunity.
      

      Herpes simplex virus structure

Herpes simplex structure

The pattern of the Herpes infection:

1. Herpesvirus 1 involves oral areas.
   1. HSV 1 is primarily responsible for oral lesions, blisters on the lip called “cold sore”.
   2. Also, there may be a corneal lesion.
2. Herpesvirus 2 involves genital areas.
   1. This is a sexually transmitted viral infection of the urogenital area.
   2. There is a vesicular lesion on the penis, scrotum, vulva, perianal region, perineum,  vagina and cervix.
3. The acute disease presents as acute gingivostomatitis (Aphthous stomatitis).
   1. This is seen in early childhood. There are vesicular lesions and fever.
   2. The dormant stage when the virus is dormant after the primary infection.
   3. The virus remains dormant in the sensory ganglia of the trigeminal nerve.
4. Eczema Herpeticum will complicate infantile eczema.
5. Keratoconjunctivitis is due to primary or is a recurrent infection.
6. Aseptic meningitis or encephalitis. The majority of these patient has high mortality reaching 70%.
7. Herpetic whitlow occurs in accidental injury to doctors, nurses, and dentists.
8. Hass’s disease or disseminated Herpes of newborn.
   1. It occurs from the mother from the infected birth canal lesions.
   2. Or it may get an infection from the transplacental spread.
   3. Mortality is very high and infants may die in a few days.
9. Vulvovaginitis is seen in children and adults.
   1. Herpes-type 2 may cause genital herpes.
      1. This remains dormant in the ganglia of the sacral plexus.
10. Congenital infection may lead to:
    1. Microcephaly.
    2. Chorioretinitis.
    3. Mental retardation.
    4. Disseminated neonatal herpes viral infection leads to a high incidence of mortality.
11. In the case of herpes infection in pregnant women, avoid vaginal delivery and cesarean section is advised.

Normal

• Culture shows no virus.
• Negative Herpes antigen or antibody.

Diagnosis:

1. Viral testing should be done on the couple to rule out the presence of herpes infection.
   1. Although accuracy is not great.
2. Smear stained with PAP  from the urethra, and cervical canal shows viral inclusions and multinucleated giant cells.
3. It can isolate the virus from the vesicles, ulcers, saliva, and CSF.
4. Serological test. These are easy and more convenient.
   1. These antigen tests’ advantage is that the results are available in a day.
   2. While the antibody tests are cumbersome, it requires a repeat blood test in acute and convalescent patients.
      1. If there is increasing titer then it is significant. A fourfold rise in the titer indicates acute infection.
      2. These patients have always high titers.
      3. The peak level after the infection is between 4 to 6 weeks.
      4. Later on, the level is low.
      5. In the USA >50% of the population is positive for herpes antibodies.
   3. Methods used are:
      1. Enzyme immunoassay (EIA).
      2. Indirect immunofluorescence (IIF).
      3. Indirect hemagglutination test.
5. Culture is the best method to confirm herpes infection.
   1. Culture is 90% positive in the positive cases.
   2. Culture positive cases are only 85% for the serological tests.
6. Method to take a sample:
   1. Sample from the urethra for culture:
      1. Insert the sterile swab in the urethra and rotate gently.
      2. Keep the patient in a lying position, check the Blood pressure, bradycardia, sweating, nausea, and weakness.
   2. Sample from the cervix for culture:
      1. A sterile speculum is inserted in the lithotomy position in the vagina.
      2. Remove the cervical mucus with a sterile cotton swab.
      3. Take a sample from the endocervical canal for culture.
      4. For pregnant women:
         1. The cervix is culture weekly, beginning 4 to 6 weeks before the due date.
         2. Vaginal delivery is possible if:
            1. The two most recent cultures are negative.
            2. There is no lesion in the vagina and vulva.
            3. There are no clinical symptoms in the pregnant lady.
            4. If throughout the pregnancy, the lady has had no more than one culture-positive and she has no symptoms.

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