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

How many different types of pseudopods can amoebas have?, Tests of shelled ...

Tests of shelled amoebas are made from a variety of substances including sand grains, chitin and substrate, calcium salts, and even silica. These shells still accumulate in ocean d

, comparitive table to explain the differences between the animals in chor...

comparitive table to explain the differences between the animals in chordate classes

Male reproductive disorders due to infections, Male reproductive disorders ...

Male reproductive disorders due to infections Septicemic infections have a greater affinity for vesicular glands than other regions of the reproductive tract viz. prostate, am

What are some prophylactic measures against hiv infection, What are some pr...

What are some prophylactic measures against HIV infection? The major prophylactic measures against HIV infection are: the use of condoms in sexual relations, not to share syrin

Fragmentation - types of asexual reproduction, Fragmentation - Types of Ase...

Fragmentation - Types of Asexual Reproduction Fragmentation is a phenomenon where parent animal spontaneously (on its own accord) splits into two or more fragments. Each one o

Dietary guidelines fur hyperlipidemic patients, Q. Dietary Guidelines fur h...

Q. Dietary Guidelines fur hyperlipidemic patients? • Calories: to maintain ideal body weight. • Carbohydrates should constitute 55-65% of calories with emphasis on • polysacc

Evaluate the moisture requirement, Evaluate the Moisture Requirement - The ...

Evaluate the Moisture Requirement - The Concept of Water Activity We already know that moisture is one of the important factors for the survival of living species. As suc

Define hexose monophosphate pathway, Define hexose monophosphate pathway ...

Define hexose monophosphate pathway The hexose monophosphate pathway (HMP also called the pentose phosphate pathway, or phoshogluconate pathway) consists of Mo irreversible o

Explain restaurant deep fat frying evaluation, Restaurant deep fat frying e...

Restaurant deep fat frying evaluation A number of factors are studied when evaluating frying oils. During deep fat frying, the fat is exposed continuously to elevated temperat

Explain th eobjective of intensive care, Explain th eobjective of intensive...

Explain th eobjective of intensive care? After reading this unit, you should be able to: • know how to organize an intensive care unit; • practice effective cardio pulmonary

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