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

Unified cell theory, Unified Cell Theory The present unified cell theo...

Unified Cell Theory The present unified cell theory states that All living things are composed of either a single Cell or of the cells and cell products. The cell is a m

What is leaf morphology, What is Leaf Morphology? Leaf Arrangemen...

What is Leaf Morphology? Leaf Arrangement : These show the different types of leaf arrangement on a twig. The point on the twig at which the leaves are attached is refer

Diseases caused by abnormal gh secretion by the hypophysis, Q. What are som...

Q. What are some diseases caused by abnormal GH secretion by the hypophysis? In childhood deficient GH secretion may lead to delayed growth and in severe cases to nanism that i

Are bacteria the only prokaryotic beings, Q Are bacteria the only prokaryot...

Q Are bacteria the only prokaryotic beings? Prokaryotic beings are classified into two big groups: bacteria and archaebacteria (this last also known as eubacteria). Compared

Explain the programmed senescence theory of ageing, Define senescence Expla...

Define senescence Explain the 'programmed senescence theory' of ageing.

Classification, what is the mode of nutrition in fungi?

what is the mode of nutrition in fungi?

Off pump coronary artery bypass surgery opcab, Application :  Off Pump...

Application :  Off Pump Coronary Artery Bypass Surgery (OPCAB) CABG is done on epicai-dial vessels. Cardio pulmonary by pass is used only to get a still h

Explain phytoestrogens, Phytoestrogens:- A group of compounds considere...

Phytoestrogens:- A group of compounds considered to offer protection against cancer.

Calculate ideal weight for a diabetic patient, Q. Calculate ideal weight fo...

Q. Calculate ideal weight for a diabetic patient? We now know that diabetes is the outcome of many genetic and environmental factors. The former is not in our control but the l

Bones, which bone forms the non-moving muscle attachment in the hip joint

which bone forms the non-moving muscle attachment in the hip joint

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