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

Movements, Normal 0 false false false EN-IN X-NONE ...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Taxonomy, what arachnid is beneficial

what arachnid is beneficial

Medical and nutritional management for pectic ulcer, Q. Medical and Nutriti...

Q. Medical and Nutritional Management for pectic ulcer? To provide physiological rest and support tissue healing, treatment should be based on providing rest to the affected ar

Write in 5-6 lines about food pyramid, Write in 5-6 lines about food pyrami...

Write in 5-6 lines about food pyramid. The diabetes food pyramid divides food into six groups. These groups vary with each other on the basis of si-e occupied in the pyramid.

Class arachnida of phylum arthropoda, Class Arachnida of Phylum Arthropoda ...

Class Arachnida of Phylum Arthropoda Body divided into cephalothorax and abdomen. Cephalothorax along with four (4) pairs of legs; abdomen segmented or unsegmented, with or wi

Define diet for treatment for protein energy malnutrition, Define Diet for ...

Define Diet for Treatment for Protein Energy Malnutrition? Treatment of cases of kwashiorkor or marasmus involves mainly providing appropriate nutrition support. The child shou

Intraspecific and interspecific competition, In the preceding block you lea...

In the preceding block you learnt the Darwinian premise of natural selection based on certain facts and deductions thereof. You would have noticed that one of the foundations for t

Plasma and its composition, PLASM A - It is slightly alkaline non-l...

PLASM A - It is slightly alkaline non-living intercellular substance which constitutes about 60% part of the blood. It is a pale yellow but transparent and clear fluid.

Describe shunts, Q. Describe Shunts? Detection, localization and quanti...

Q. Describe Shunts? Detection, localization and quantification of intracardiac shunts are one of the most important exercises in cardiac catheterization. In most cases a prelim

Disease control and prevention reports, Disease Control and Prevention repo...

Disease Control and Prevention reports: Body Mass Index is a reliable indicator of body fat for most children and teens. BMI is calculated from a  child's weight and height is

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