Reappraisal of the Role of Ascitic Fluid Adenosine Deaminase for the Diagnosis of Peritoneal Tuberculosis in Cirrhosis

Utility of human epididymis protein 4 in the differential diagnosis of ascites

BACKGROUND AND AIMS

Human epididymal protein 4 (HE4) may be a useful tool in the differential diagnosis of malignant ascites. The aim of this study was to evaluate the diagnostic utility of HE4 for detecting malignant ascites, taking into account the possible false positives identified with adenosine deaminase (ADA), C-reactive protein (CRP), % polynuclear cells (%PMN) and glomerular filtration rate (eGFR).

METHODS

Concentrations of HE4, ADA, %PMN and CRP were determined in 114 samples of peritoneal fluid and creatinine in serum in order to calculate eGFR.

RESULTS

Concentrations of HE4 presented significant differences (P = 0.028) in benign [median (interquartile range)] [582(372)] pmol/L) and malignant ascites ([8241(367)] pmol/L. Sensitivity was 21.2% and specificity 100%. Significant differences were also observed for HE4 between tumors of gynecological origin ([3165(8769)] pmol/L) and others ([665(663)] pmol/L), with a sensitivity of 67% and a specificity of 100%. Classifying according to possible false positives (ADA > 45U/L, CRP > 50 mg/L, %PMN > 90 and eGFR < 30 mL/min/1.73 m2) at maximum specificity, a sensitivity of 33.3% was obtained for HE4, with a cut-off point of 2660 pmol/L. Without possible false positives (ADA < 45U/L, CRP < 50 mg/L, %PMN < 90 and eGFR ≥ 30 mL/min/1.73 m2), a sensitivity of 37.7% was obtained at 100% specificity for a cut-off point of 1041 pmol/L. Applying these criteria to the entire group, a sensitivity of 36.4% was obtained at maximum specificity.

CONCLUSIONS

HE4 allows the identification of malignant ascites with moderate sensitivity at maximum specificity. HE4 levels can differentiate between tumors of gynecological origin and others. Classification according to possible false positives increases sensitivity without losing specificity.

An Updated Systematic Review and Meta-Analysis for the Diagnostic Test Accuracy of Ascitic Fluid Adenosine Deaminase in Tuberculous Peritonitis

BACKGROUND

Tuberculous peritonitis is difficult to diagnose due to its non-specific clinical manifestations and lack of proper diagnostic modalities. Current meta-analysis was performed to find the overall diagnostic accuracy of adenosine deaminase (ADA) in diagnosing tuberculous peritonitis.

MATERIALS AND METHODS

PubMed, Google Scholar, and Cochrane library were searched to retrieve the published studies which assessed the role of ascitic fluid ADA in diagnosing tuberculous peritonitis from Jan 1980 to June 2022. This meta-analysis included 20 studies and 2,291 participants after fulfilling the inclusion criteria.

RESULTS

The pooled sensitivity was 0.90 (95% confidence interval [CI]: 0.85 - 0.94) and pooled specificity was 0.94 (95% CI: 0.92 - 0.95). The positive likelihood ratio was 15.20 (95% CI: 11.70 - 19.80), negative likelihood ratio was 0.10 (95% CI: 0.07 - 0.16) and diagnostic odds ratio was 149 (95% CI: 86 - 255). The area under the summary receiver operating characteristic curve was 0.97. Cut- off value and sample size were found to be the sources of heterogeneity in the mete-regression analysis.

CONCLUSION

Ascitic fluid ADA is a useful test for the diagnosis of tuberculous peritonitis with good sensitivity and specificity however, with very low certainty of evidence evaluated by Grading of Recommendations, Assessment, Development and Evaluation approach. Further well- designed studies are needed to validate the diagnostic accuracy of ascitic fluid ADA for tuberculous peritonitis.

Diagnostic performance of adenosine deaminase for abdominal tuberculosis: A systematic review and meta-analysis

Background and aim

Abdominal tuberculosis (TB) is a common type of extrapulmonary TB with an insidious onset and non-specific symptoms. Adenosine deaminase (ADA) levels increase rapidly in the early stages of abdominal TB. However, it remains unclear whether ADA serves as a diagnostic marker for abdominal TB.

Methods

We performed a systematic literature search for relevant articles published in PubMed, Web of Science, Cochrane Library, and Embase up to April 2022. First, we used the Quality Assessment of Diagnostic Accuracy Studies tool-2 (QUADAS-2), to evaluate the quality of the included articles. Bivariate and hierarchical summary receiver operating characteristic (HSROC) models were then utilized to analyze pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and area under the receiver operating characteristic curve (AUROC). In addition, we explored a subgroup analysis for potential heterogeneity and publication bias among the included literature.

Results

Twenty-four articles (3,044 participants, 3,044 samples) which met the eligibility criteria were included in this study. The pooled sensitivity and specificity of ADA for abdominal TB detection were 93% [95% confidence interval (CI): 0.89-0.95] and 95% (95% CI: 0.93-0.96), respectively. PLR and NLR were 18.6 (95% CI: 14.0-24.6) and 0.08 (95% CI: 0.05-0.12), respectively. DOR and AUROC were 236 (95% CI: 134-415) and 0.98 (95% CI: 0.96-0.99), respectively. Furthermore, no heterogeneity or publication bias was found.

Conclusions

Our meta-analysis found ADA to be of excellent diagnostic value for abdominal TB and could be used as an auxiliary diagnostic tool.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42022297931.