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LETTER TO EDITOR |
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| Year : 2022 | Volume
: 43
| Issue : 2 | Page : 238-240 |
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Accuracy of Gram-stained smears as screening tests for Neisseria gonorrhoeae: Brief communication
Mohamed Abdalla Khalid
Department of Laboratory, Kamal Medical Polyclinics, Riyadh, Saudi Arabia
| Date of Submission | 06-Dec-2020 |
| Date of Decision | 28-Feb-2022 |
| Date of Acceptance | 02-Mar-2022 |
| Date of Web Publication | 17-Nov-2022 |
Correspondence Address:
Dr. Mohamed Abdalla Khalid
Department of Laboratory, Kamal Medical Polyclinics, Riyadh
Saudi Arabia
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/ijstd.ijstd_132_20
How to cite this article:
Khalid MA. Accuracy of Gram-stained smears as screening tests for Neisseria gonorrhoeae: Brief communication. Indian J Sex Transm Dis 2022;43:238-40 |
How to cite this URL:
Khalid MA. Accuracy of Gram-stained smears as screening tests for Neisseria gonorrhoeae: Brief communication. Indian J Sex Transm Dis [serial online] 2022 [cited 2023 Sep 28];43:238-40. Available from: https://ijstd.org/text.asp?2022/43/2/238/361309 |
Sir,
Neisseria gonorrhoeae (Ng) is an etiologic agent of gonorrhea, one of the most common sexually transmitted diseases caused by bacteria. Which has an estimated global annual incidence of 86.9 million adults.[1] A presumptive gonorrhea diagnosis can be made based on light microscopic detection of the bacterium in Gram-stained smears (GSS). This enables immediate treatment, thus preventing ongoing transmission and/or loss to follow-up.[2]
The present study reviewed the diagnostic accuracy variables (sensitivity, specificity, likelihood ratios [LRs], and diagnostic odds ratios [DORs]) of gram GSS that screen for Ng in urethral swabs and endocervical swabs specimens. Author evaluated studies conducted worldwide in adults by searching MEDLINE (through PubMed) from 1980 to 2020. This study included studies conducted in adult humans if they provided enough raw data to recreate the 2 × 2 diagnostic tables. The author did not exclude articles on the basis of study location or study design. [Figure 1] shows a flowchart of the search. The author conducted the searches and screened articles for eligibility. After initial identification of all studies and deletion of duplicates, the author did a preliminary screening of 937 articles based on title and abstract. Of which, 26 were considered for full-text review. Eleven articles were retrieved and included in the study.
The present study assessed the methodological and reporting quality of studies using the (Quality Assessment of Diagnostic Accuracy Studies 2) tool [Figure 2]. All statistical analyses were carried out in Intercooled Stata, version 15 (StataCorp, College Station, Texas, USA). The sensitivity, specificity, positive LR, negative LR, and DOR were calculated [Table 1] and [Table 2]. LRs of a test inform the pretest probability of disease and provide a posttest probability. A positive LR higher than 5 and a negative LR <0.2 provide strong diagnostic evidence.[14] | Table 2: Results of meta-analysis, by specimen and reference standard subgroup
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Of the 11 total studies, 3 (27%) were conducted in developing settings[3],[12],[13] and 8 (73%) were conducted in developed settings.[4],[5],[6],[7],[8],[9],[10],[11] Sample sizes ranged from 95 to 27,600 persons.
To interpret study results, first, reference standards were found to influence the accuracy of GSS.[15] Second, the effect of antimicrobial susceptibility testing on diagnostic accuracy is worth further consideration.[16] Third, the index tests included in this study detected intercellular diplococcus Ng and therefore could not detect infection within about 2–10 days.[17] Finally, evidence on GSS will be of greater use to policymakers and guideline developers if outcomes beyond accuracy are documented.
In conclusion, GSS offers many advantages: A fast turnaround time, declaration of results at the point of care with the potential for affecting clinical management, and early detection of undiagnosed cases of gonorrhea.[18] This study found GSS to be accurate and suitable for screening initiatives.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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| 14. | Jaeschke R, Guyatt GH, Sackett DL. Users' guides to the medical literature. III. How to use an article about a diagnostic test. B. What are the results and will they help me in caring for my patients? The evidence-based medicine working group. JAMA 1994;271:703-7. |
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[Figure 1], [Figure 2]
[Table 1], [Table 2]
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