Question

Barbara F., a 30-year- old woman, presented to her physician with symptoms of weigh t loss, painful joints, malaise e, low-grade fever, a skin rash, and swollen glands that were not painful.

Serology

Rapid plasma regain: Positive

QUESTIONS

1. What disease/infection does the abnormal result indicate?

2. What is the causative organism? Briefly describe this organism.

3. List three other closely related species and the associated disease.

4. List and briefly discuss (include time frame and symptoms) the four stages of this disease. At what stage would she be classified?

                                                5. What antibody is detected by the RPR? Is it specific for this disease?

6. List five conditions that are associated with biological false-positive RPRs.

7. What would the physician do next to confirm this diagnosis? ls one RPR sufficient.

8. List and briefly describe four confirmatory tests for this disease. What anti­ bodies are detected by these tests?

9. What test is routinely used to test spinal fluid for this condition? What does this test detect?

10. Which stage of this disease can be missed by the RPR?

11. What is the treatment of choice for this condition?

Answer 1

1. Syphilis

2. Treponema pallidum

Treponema pallidum is a spirochaete bacterium with various subspecies that cause the diseases syphilis, bejel, and yaws. It is transmitted only amongst humans.It is a helically coiled microorganism usually 6–15 μm long and 0.1–0.2 μm wide. T. pallidum's lack of metabolic pathways (tricarboxylic acid cycle, oxidative phosphorylation) results in minimal metabolic activity.^] The treponemes have a cytoplasmic and an outer membrane.

3. Borrelia bissettii - Lyme borreliosis

Borrelia recurrentis - Louse-borne relapsing fever

Treponema pallidum pertenue - Yaws

4.

Stages of syphilis infection

The four stages of syphilis are:

• primary
• secondary
• latent
• tertiary

Syphilis is most infectious in the first two stages.

When syphilis is in the hidden, or latent, stage, the disease remains active but often with no symptoms. Tertiary syphilis is the most destructive to health.

Primary syphilis

he primary stage of syphilis occurs about three to four weeks after a person contracts the bacteria. It begins with a small, round sore called a chancre. A chancre is painless, but it’s highly infectious. This sore may appear wherever the bacteria entered the body, such as on or inside the mouth, genitals, or rectum.

On average, the sore shows up around three weeks after infection, but it can take between 10 and 90 days to appear. The sore remains for anywhere between two to six weeks.

Syphilis is transmitted by direct contact with a sore. This usually occurs during sexual activity, including oral sex.

Secondary syphilis

Skin rashes and a sore throat may develop during the second stage of syphilis. The rash won’t itch and is usually found on the palms and soles, but it may occur anywhere on the body. Some people don’t notice the rash before it goes away.

Other symptoms of secondary syphilis may include:

• headaches
• swollen lymph nodes
• fatigue
• fever
• weight loss
• hair loss
• aching joints

These symptoms will go away whether or not treatment is received. However, without treatment, a person still has syphilis.

Secondary syphilis is often mistaken for another condition.

Latent syphilis

The third stage of syphilis is the latent, or hidden, stage. The primary and secondary symptoms disappear, and there won’t be any noticeable symptoms at this stage. However, the bacteria remain in the body. This stage could last for years before progressing to tertiary syphilis.

Tertiary syphilis

The last stage of infection is tertiary syphilis. According to the Mayo Clinic, approximately 15 to 30 percent of people who don’t receive treatment for syphilis will enter this stage. Tertiary syphilis can occur years or decades after the initial infection. Tertiary syphilis can be life-threatening. Some other potential outcomes of tertiary syphilis include:

• blindness
• deafness
• mental illness
• memory loss
• destruction of soft tissue and bone
• neurological disorders, such as stroke or meningitis
• heart disease
• neurosyphilis, which is an infection of the brain or spinal cord

She,the patient can be classified at the stage two,Secondary syphilis

.5. Usually react with IgM and IgG6.

6. Five conditions that are associated with biological false-positive RPR

-HIV

-Lyme disease

-Malaria

-Lupus

-Certain types of pneumonia

7. Due to risk of false positive results,doctor will confirm the presence of syphilis with a second test,one that is FTA-ABS.

No,one RPR is not sufficient.

8. Four confirmatory tests for Syphilis

The VDRL and USR tests are microflocculation tests and are read under a microscope. A disadvantage of the VDRL test is that the antigen suspension must be prepared fresh daily, whereas the USR test uses a stabilized antigen. However, the VDRL test is the only nontreponemal test that can be used to test CSF due to the limited sensitivity and specificity of the other nontreponemal tests. The RPR and TRUST tests are macroscopic flocculation tests and require no microscope. The RPR test uses a stabilized suspension of VDRL antigen to which charcoal particles are added to aid in the visualization of the test reaction. The RPR test is one of the most commonly used nontreponemal tests, and is a simplified version of the VDRL test. In the TRUST test, particles of toluidine red are used in place of the charcoal particles of the RPR test. Each of the above tests can be used as a quantitative test. Quantitative tests  allow for the establishment of a baseline titre, which allows evaluation of recent infection and response to treatment. This also allows for the detection of reinfection or relapse in persons with a persistently reactive titre. However, the numerical values obtained may vary between tests; thus, when a patient is being followed with serial titres, the same test and preferably the same laboratory should be used.

Fluorescent treponemal antibody absorption test and fluorescent treponemal antibody absorption double staining tests

The fluorescent treponemal antibody absorption (FTA-ABS) test is an indirect fluorescent antibody technique. In this procedure, serum samples are pretreated with an absorbent to remove nonspecific antibodies. The FTA-ABS double staining test is a modification of the FTA-ABS test using a double staining procedure with the addition of a contrasting counterstain. While these tests are highly sensitive and specific, they may produce variable results due to variation in equipment, reagents and interpretation

TP-PA test

The Treponema pallidum particle agglutination (TP-PA) test (Fujirebio Inc, Japan) is a qualitative assay for the detection of antibodies to T pallidum in serum or plasma. This test is based on the agglutination of coloured particle carriers sensitized with T pallidum antigen and has replaced its predecessor, the microhemagglutination assay - Treponema pallidum (MHA-TP, Fujirebio Inc, Japan). The TP-PA test uses the same treponemal antigen as the MHA-TP test but offers the advantage of gelatin particles instead of erythrocytes, thus eliminating nonspecific reactions with plasma samples. The TP-PA test is less expensive and less complicated than the FTA-ABS tests, and the results are read with the unaided eye. It is one of the more commonly used treponemal tests. A positive TP-PA test in conjunction with a positive nontreponemal test is indicative of current or past infection with T pallidum. The TP-PA test - found to be an appropriate substitute for the MHA-TP test (8) - is as sensitive as the FTA-ABS test in primary syphilis and as useful as the RPR test in monitoring therapy

Dark-field microscopy

This method still remains one of the simplest and most reliable for the direct detection of T pallidum. Exudates and fluids from lesions are examined as a wet mount using dark-field microscopy. The identification of T pallidum is based on the characteristic morphology and motility of the spirochete. This method is suitable when the lesions are moist, and the examination can be done immediately after specimen collection. During the primary stage, serous fluid from the lesion contains numerous treponemes and, therefore, this approach is particularly useful in patients with immunodeficiency or in early syphilis when antibodies are not yet detectable. However, this technique requires a trained, experienced microscopist. Success is dependent on a number of factors, including too little or too much fluid on the slide, the presence of refractile elements in the specimen, improper thickness of the slide or cover slip, etc. Treatment with antibiotics may result in a false-negative finding. Therefore, although the demonstration of T pallidum is the definitive method of diagnosis, dark-field microscopy has limited sensitivity, and failure to detect T pallidum by this test does not rule out syphilis.

9. VDRL is routinely used to test spinal fluid for this condition.

VDRL test is the test that can be used to test CSF due to the limited sensitivity and CSF testing indicate congenital and tertially syphilis.

10. The third stage- latent syphilis

11. Treatment of choice

Primary and secondary syphilis are easy to treat with a penicillin injection. Penicillin is one of the most widely used antibiotics and is usually effective in treating syphilis. People who are allergic to penicillin will likely be treated with a different antibiotic, such as:

• doxycycline
• azithromycin
• ceftriaxone

If you have neurosyphilis, you’ll get daily doses of penicillin intravenously. This will often require a brief hospital stay. Unfortunately, the damage caused by late syphilis can’t be reversed. The bacteria can be killed, but treatment will most likely focus on easing pain and discomfort.

During treatment, make sure to avoid sexual contact until all sores on your body are healed and your doctor tells you it’s safe to resume sex. If you’re sexually active, your partner should be treated as well. Don’t resume sexual activity until you and your partner have completed treatment.