Identification of orcinol reactive substance in pleural fluid cell lysate--a new parameter for classification of pleural effusion.
BACKGROUND
Cell-free DNA is observed to be more in exudative pleural effusions. Based on this fact development of a clinical chemistry test for classification of pleural effusion will require DNA extraction followed by PCR amplification and electrophoresis. These procedures may not be cost effective for the purpose for classification of pleural effusion as already established parameters are popular for the purpose which can be estimated by comparatively low cost colorimetric procedures. Therefore development of a simple colorimetric test for the classification of pleural fluid based on nucleic acid identification test can be attempted. The aim of this work is to develop such colorimetric test for classification of pleural effusion using only pleural fluid sample.


METHODS
Cell pellet is obtained from 5 ml pleural fluid which is lysed and subjected to DNA extraction, followed by identification under UV-transilluminator after electrophoresis and orcinol and diphenylamine reaction.


RESULTS
Exudates show extractable DNA from 5 ml biofluid (n=52) which are not observed from transudate (n=32). Orcinol reaction is significantly positive in exudates (n=52) compared to the transudates (n=32). Diphenylamine test cannot differentiate exudate from transudate.


CONCLUSIONS
Orcinol reaction of cell lysate obtained from pleural fluid can classify pleural fluid sample into exudate or transudate.
Department of Biochemistry, Calcutta National Medical College, Kolkata-700014, India.
Subendu
S
Sarkar
Gorachand
G
Bhattacharya
Subir
S
Bandyopadhyay
Soumya
S
Bhattacharjee
Dibyajyoti
D
Banerjee
D000293:Adolescent; D000328:Adult; D000368:Aged; D001798:Blood Proteins / Q000378:metabolism; D002477:Cells / Q000737:chemistry*; D002648:Child; D003937:Diagnosis, Differential; D004159:Diphenylamine / Q000737:chemistry; D005122:Exudates and Transudates / Q000166:cytology* / Q000201:enzymology / Q000378:metabolism; D005260:Female; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000097:blood / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009696:Nucleic Acids / Q000032:analysis / Q000737:chemistry; D010996:Pleural Effusion / Q000097:blood / Q000175:diagnosis*; D012118:Resorcinols / Q000737:chemistry; D055815:Young Adult
D001798:Blood Proteins; D009696:Nucleic Acids; D012118:Resorcinols; C005282:orcinol; D004159:Diphenylamine; D007770:L-Lactate Dehydrogenase