Etiology, Biology

Assignment Help:

M protein of rheumatogenic GAS has distinct structural characteristics that are akin to human heart tissue, particularly sarcolemmal membrane proteins and cardiac myosin. The major factors that lead to risk of ARF are the severity of the immune response to GAS pharyngitis and persistence of GAS organisms during convalescence. A very small proportion (0.3-3 per cent) of patients suffering from GAS throat infection ultimately develop ARF and this along with a familial predisposition of ARF points to a genetic susceptibility. However, in our Indian patients a genetic linkage to HLA DR3 in patients, with ARF has been demonstrated. For confirmation of the initial diagnosis of acute rheumatic fever, evidence of prior GAS infection is required. Several rapid GAS antigen tests are available. Majority of these tests has a high degree of specificity but low level of sensitivity in clinical practice.

However, it must be stressed that a negative test does not rule out the GAS infection in the throat. At the same time in presence of a positive antigen test and positive throat culture, it is difficult to distinguish between a recent infection which can be associated with ARF and chronic carrier of GAS infection with ARF. Elevated or rising ASO titres (> 250Todd units in adults and >333 Todd units in children) are more reliable evidence of recent GAS infection than a positive culture or positive rapid antigen test and such titres are also significant for diagnosis.


Related Discussions:- Etiology

Reflexes related to respiration, SOM E COMMON REFLEXES RELATED TO RESPIRAT...

SOM E COMMON REFLEXES RELATED TO RESPIRATION - 1.      Cough Reflex: Due to stimulation in Trachea before it 2.5 lit. air is inhaled. 2.      Sneezing Reflex: Stimulati

Explain cardiopulmonary resuscitation, Explain Cardiopulmonary Resuscitatio...

Explain Cardiopulmonary Resuscitation? The heart rhythm associated with cardiac arrest can be either ventricular fibrillation/ ventricular tachycardia (VT/VF) or other rhythms

Name the enzyme included in the continuous replication, Mention the informa...

Mention the information that the health workers get by measuring BOD of a water Body. a) Name the enzyme included in the continuous replication of DNA strand. Mention the Polar

Evolution the eukaryotic cell or the prokaryotic cell, Which type of cell c...

Which type of cell came first in evolution the eukaryotic cell or the prokaryotic cell? Ans) This is an interesting problem of biological evolution. The most accepted hypothesis

What are coacervates, What are coacervates what property do they have that ...

What are coacervates what property do they have that suggests they could be a primitive cell.

What do you understand by herbarium ethics, Q. What do you understand by He...

Q. What do you understand by Herbarium ethics? You should also know that herbaria provide us with policy statements including such information as 1) filing arrangements, 2) res

How gender affects the bmr, How Gender affects the bmr? We have already...

How Gender affects the bmr? We have already emphasized earlier that sex difference in metabolic rates are primarily attributable to difference in body size and composition. Wom

Define briefly about the manganese toxicity, Define Briefly about the Manga...

Define Briefly about the Manganese Toxicity? Manganese is considered least toxic of the trace minerals through oral intake. However, some people may be at a risk to develop tox

Energy requirements of school children and adolescents, Determine Energy re...

Determine Energy requirements of school children and adolescents? Table depicts the energy requirements of school children and adolescents,  as recommended by ICMR (1990).

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd