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04:25
Capsular Serotyping of Streptococcus pneumoniae Using the Quellung Reaction
Published on: February 24, 2014
Streptococcal serotypes newly associated with epidemic post-streptococcal acute glomerulonephritis
H F Reid1, D C Bassett, E Gaworzewska
1Trinidad and Tobago Public Health Laboratory, Port of Spain, West Indies.
Journal of Medical Microbiology
|June 1, 1990
Summary
An increase in scabies cases prompted monitoring of post-streptococcal acute glomerulonephritis (PSAGN). The 1986 PSAGN epidemic involved new M-types 73, 48, and PT 5757 in its first wave, and M-type 55 in the second.
Area of Science:
- Epidemiology
- Microbiology
- Public Health
Background:
- Rising scabies incidence in Trinidad necessitated monitoring of post-streptococcal acute glomerulonephritis (PSAGN).
- PSAGN is a serious complication following streptococcal infections.
Purpose of the Study:
- To investigate the etiological agents of a PSAGN epidemic in Trinidad in 1986.
- To identify specific streptococcal M-types and provisional types (PTs) associated with the epidemic.
Main Methods:
- Monitoring of 181 PSAGN patients in 1986.
- Collection and laboratory analysis (grouping and serotyping) of 84 beta-hemolytic streptococcal isolates from 72 patients.
- Comparison of isolates with previously identified strains from the UK and Germany.
Main Results:
- The 1986 PSAGN epidemic exhibited a bimodal pattern.
- The first wave (March-May) was associated with M-type 73 (20%), M-type 48 (4%), and PT 5757 (14%).
- M-type 48 and PT 5757 were identified for the first time in Trinidad.
- The second, more intense wave (July-October) was linked to the nephritogenic M-type 55.
Conclusions:
- The Trinidad PSAGN epidemic involved multiple streptococcal M-types and provisional types.
- M-type 55 was the primary cause of the second, more severe epidemic phase.
- The emergence of new M-types (48, PT 5757) alongside established types (73, 55) highlights evolving epidemiology.
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