Spirochetes MCQs

This patient displays the hallmarks of a classical anaphylactic reaction to penicillin. Anergy is the impairment of effector immune responsiveness. Antibody-mediated cytotoxicity is most often localized to tissues bearing epitopes to which the antibody binds. Contact sensitivity results from the epicutaneous application of a reactive antigen/hapten; in the present question, the antigen (penicillin) was administered intramuscularly. Reference: Ananthanarayan and Paniker's Textbook of Microbiology 10th edition Chapter 16, Pg 164-168

Ans. is 'a' i.e.,Syphilis [Ref Harrison 18th/e p. 1382, Jawetz 22"/e p. 642] Painless indurated ulcer with everted margins, h/o of sexual exposure and lack of systemic symptoms favours the diagnosis of syphilis.

Non-treponemal tests, such as VDRL and RPR are preferred over treponemal tests for monitoring response to treatment. Antibody titers of treponemal tests remain elevated even after clinical improvement. VDRL has to be done at 3 month's intervals for at least 1 year. For primary and secondary syphilis: Following clinical improvement, there should be at least a fourfold decline in the titer by the third or fourth month and non-reactive by 12 months. For latent or late syphilis, or patients with multiple episodes of syphilis: It may show a gradual decline in titer, low titers may persist for years. Here, Non treponemal tests are negative hence the treatment to the mother was effective. Reference: Essentials of Medical Microbiology, by Apurba Sastry and Sandhya Bhat, 3rd edition, page no. 761

Spirochetes are spiral shaped bacteria. Medically important spirochetes are Treponema, Borrelia and Leptospira. Smith Noguchi's medium is used for cultivation of non-pathogenic Treponemes (Pathogenic Treponemes cannot be grown in artificial culture medium) Reference : Ananthanarayan and Paniker's Textbook of Microbiology 10th edition Chapter 4, Pg 40-45

Parvovirus B19, can lead to the development of hydrops fetalis during pregnancy. Infection of RBCs by this virus induces apoptosis and massive destruction of erythroid lineage cells, causing severe anemia and heart failure in the fetus (secondary to excessive fluid accumulation within the fetal vascular compartments). This often-fatal condition can also be caused by chromosomal abnormalities, inborn errors of metabolism, Rh incompatibility, lymphatic dysplasia, and Treponema pallidum infection. Other Options: Chorioretinitis is seen with Toxoplasma gondii or CMV infection Sensorineural deafness is seen with CMV, Rubella or Syphilis Vesicular rash is seen with HSV2 infection Reference: Essentials of Medical Microbiology, by Apurba Sastry and Sandhya Bhat, 3rd Edition, Page Number 550

High fever, myalgia, and headache are common clinical manifestations of leptospirosis. Leptospirosis can be associated with acute abdominal pain, sometimes mimicking acute cholecystitis; however, diarrhea rarely occurs. Localized seizure would be an atypical presentation of leptospirosis, which is generally not considered to be associated with focal neurologic findings. Reference : Harrison's Principles of Internal Medicine, 21 st Ed, Ch: 184 Pg: 1419 Goldman Cecil's Medicine 26th Ed. Chap 307 pg. 1999