Indian Journal of Rheumatology

ORIGINAL ARTICLE
Year
: 2018  |  Volume : 13  |  Issue : 3  |  Page : 159--162

Comparison of the performance of three classification criteria for Behçet's Disease in a single centre cohort from South India


Vishnu S Chandran1, Suma Balan2,  
1 Department of Rheumatology, Amrita Institute of Medical Sciences, Kochi, Kerala, India
2 Department of Paediatric Rheumatology, Amrita Institute of Medical Sciences, Kochi, Kerala, India

Correspondence Address:
Dr. Suma Balan
Department of Pediatric Rheumatology, Amrita Institute of Medical Sciences, Kochi, Kerala
India

Abstract

Background: A new International Paediatric criteria for Behçet's disease (PEDBD) 2015 has been introduced in the presence of existing revised International Criteria for Behçet's Disease (ICBD) and the International Study Group (ISG) criteria. In this study, we compared the performance of the new PEDBD criteria with the existing criteria in the pediatric group of Behçet's disease. Methods: In this retrospective study eligible patients were identified from a database and their already recorded characteristics were analyzed. A total of 25 patients who visited the pediatric rheumatology clinic were included in the cohort. Performance of the ISG, revised ICBD, and PEDBD 2015 was evaluated in terms of sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), negative likelihood ratio (NLR), positive likelihood ratio (PLR), diagnostic odds ratio (DOR), accuracy, and Youden's index (YI). Results: The revised ICBD has the maximum sensitivity (88.24%) when compared to PEDBD (64.71%) and ISG (47.05%). ISG had 100% specificity, with a comparable value in revised ICBD (87.5%) and PEDBD (87.5%). PPV was similar in all the three criteria with ISG 100%, revised ICBD 93.75%, and PEDBD 91.67%. NPV in revised ICBD was 77.78%, ISG was 47.06%, and PEDBD 53.85%. PLR of revised ICBD was 7.06 and PEDBD was 5.18. NLR was detected to be 0.53 in ISG as it was 0.40 in PEDBD and 0.13 in revised ICBD. The DOR in revised ICBD was 52 and PEDBD was 12.83. YI was 0.47 in ISG, 0.76 in revised ICBD, and 0.52 in PEDBD. The accuracy was best for revised ICBD 88% and PEDBD 72%. Conclusion: Revised ICBD criteria hold a higher statistical significance in the diagnosis of the Behçet's disease even in the pediatric age group. PEDBD has a comparable sensitivity and PPV although the NPV and specificity are very low in comparison to the other criteria. It was observed that oral aphthosis, despite being the most common manifestation in the Behçet's disease pediatric group, other features, mainly vascular involvement was the most common presenting complaint.



How to cite this article:
Chandran VS, Balan S. Comparison of the performance of three classification criteria for Behçet's Disease in a single centre cohort from South India.Indian J Rheumatol 2018;13:159-162


How to cite this URL:
Chandran VS, Balan S. Comparison of the performance of three classification criteria for Behçet's Disease in a single centre cohort from South India. Indian J Rheumatol [serial online] 2018 [cited 2019 May 24 ];13:159-162
Available from: http://www.indianjrheumatol.com/text.asp?2018/13/3/159/234006


Full Text



 Introduction



Behçet's disease (BD) is a chronic systemic variable vessel vasculitis [1] which is well known for multisystem, relapsing nature, and absence of a pathognomonic feature. Despite having more than 17 accepted criteria [2] for the disease process, a revision was inevitable. The most acceptable criteria among them are the criteria of the international study group (ISG) for BD [3] and revised International Classifications Criteria for BD (revised ICBD)[4] 2010 with variable performance. A pediatric criteria for BD 2015 (PEDBD)[5] is a recently introduced classification criterion for BD in a pediatric group with promising sensitivity. The difference from revised ICBD is the exclusion of pathergy test and the weight given to each clinical feature.[5] In adults, revised ICBD demonstrated an unbiased estimate of the sensitivity of 94.8%, considerably higher than that of the ISG criteria (85.0%), and specificity (90.5%) was lower than that of the ISG-criteria (96.0%), yet reasonably high in validatory studies.[4] The new international PEDBD classification also demonstrated a higher sensitivity (91.7%) but lower specificity (42.9%) in comparison to the ISG criteria.[5]

The objective of the study is to compare the performance of PEDBD with criteria of ISG and revised ICBD criteria.

 Methods



In this retrospective study eligible patients were identified from a database and their already recorded characteristics were analyzed. A total of 25 patients who visited the pediatric rheumatology clinic were included in the cohort. The clinical features were validated with the concerned specialist. Oral aphthosis, genital aphthosis, and skin manifestations, namely papulopustular rash and erythema nodosum were diagnosed in conjunction with a clinical opinion from the dermatologist. Ophthalmologic manifestations such as uveitis and retinal vasculitis were confirmed by the ophthalmologist in the retina clinic. The Behçet's disease can affect blood vessels, both arterial and venous, of any calibre. Any suspicious vascular involvement was identified and confirmed with radiological guidance by a radiologist. Gastrointestinal involvement was identified with the endoscopic procedure. Adequate biopsies were taken from skin and gastrointestinal tract to confirm the histopathologic appearance and exclude mimics. Pathergy tests were performed and read in the rheumatology and dermatology outpatient departments. The diagnosis of BD was made on clinical grounds as defined by the experts.

Statistical analysis

The data were entered and analyzed with Microsoft Excel software version 2010 and SPSS statistics software version 17.0. Performance of the ISG, revised ICBD 2010 and PEDBD 2015 were evaluated in terms of sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), negative likelihood ratio (NLR), positive likelihood ratio (PLR), diagnostic odds ratio (DOR), Accuracy and Youden's index (YI).

Ethical approval

This study was approved by the ethics committee of the institute.

 Results



This study included 17 patients who were diagnosed with BD and 8 patients who had symptoms that mimic BD. The majority of the patients were females. [Table 1] shows the demographic data.{Table 1}

The clinical manifestations in the true BD group are described in [Table 2]. None of the patients had neurologic involvement. Two out of 17 was detected to have relapsing polychondritis. Despite having an oral ulcer as the most common clinical manifestation the majority of patients had vascular manifestations, genital ulcers and skin manifestation as the presenting complaints.{Table 2}

In the study the revised ICBD has the maximum sensitivity 88.24% (95% confidence interval [CI]: 63.56%–98.54%) when compared to PEDBD 64.71% (95% CI: 38.33%–85.79%) and ISG 47.05% (95% CI: 22.98%–72.19%). ISG had 100% specificity (95% CI: 63.06%–100%) with a comparable value in revised ICBD 87.5% (95% CI: 47.35%–99.68%) and PEDBD 87.5% (95% CI: 47.35%–99.68%).

The PPV was similar in all the three criteria with ISG 100 %, revised ICBD 93.75% (95% CI:47.35%–99.68%), PEDBD 91.67% (95% CI: 62.98%–98.61%). NPV in revised ICBD was 77.78% (95% CI: 48.12%–92.96%), ISG was 47.06% (95% CI: 36.22%–58.19%) and PEDBD 53.85% (95% CI: 36.80%–70.04%). The Accuracy was best for revised ICBD 88% (95% CI: 68.78%–97.45%), and PEDBD 72% (95% CI: 50.61%–87.93%), were as it was only 64% (95% CI: 42.52%–82.03%) in ISG. PLR is comparable among the revised ICBD and PEDBD criteria. NLR was best in ISG. The highest DOR was for revised ICBD criteria. YI was highest in revised ICBD when comparing with ISG and PEDBD criteria. The PLR, NLR, DOR and Youdens index are shown in the [Table 3].{Table 3}

 Discussion



In the study conducted in the pediatric Behçet's cohort in a single center in south India, we tried to validate the new classification criteria, PEDBD and compare its performance with the existing classification criteria, the ISG and revised ICBD criteria. The study shows that there is probably geographic variation in the clinical presentation. Majority of patients were females even when the gender distribution is shown equal in various multicentric studies.[6] Even though the most common clinical manifestation is oral aphthosis,[5] vascular manifestations, skin manifestations and genital aphthosis were the most common clinical features to provoke patients to seek medical help. To our surprise, 5 patients, despite being definite BD, had never had a history of chronic oral aphthosis.

We found that, in terms of performance of the classification criteria's, revised ICBD (2010) outruns other criteria's. It was found to have the best sensitivity, PPV, NPV, PLR, DOR, YI and accuracy. The Specificity was also significantly high enough to serve its purpose. However PEDBD also was found to be at par with the revised ICBD criteria in terms of specificity, PPV, PLR but there was a significant difference in terms of sensitivity, NPV, YI and DOR. Accuracy was intermediate when comparing with other criteria's.

It wouldn't be surprising to have a comparable result of the new classification criterion with ICBD as both criterions differ only in the weightage given for various clinical parameters and removal of pathergy test for the diagnosis of BD. The use of Pathergy test was found to be noncontributory in the diagnosis of BD in the pediatric cohort we used.[5] Gastrointestinal manifestations were seen in eight out of 17 patients with BD of which 5 were found to have false negative PEDBD. The gastrointestinal manifestations do not have enough weightage in the current diagnostic criteria's along with arthritis even when it has shown more frequent presentation in the BD.

In comparison with the previous studies, all the three criteria have a lower sensitivity. ISG criteria show a trend in the performance similar to older studies,[2],[4],[7],[8] but it is noteworthy that the sensitivity of the ISG criteria has dropped below 50% in our study. The revised ICBD criterion has a lower sensitivity and specificity too upon comparing with the older study.[2],[4],[7],[8] This could be probably due to the small cohort or a geographic variation as mentioned earlier. The discriminative power of the various criterions was evaluated with DOR, Accuracy and Youden's Index and revised ICBD was showing a power similar to the one seen in older studies.[2],[4],[7],[8] The sensitivity and specificity from previous studies are given in [Table 4] and [Table 5] respectively.{Table 4}{Table 5}

The major limitation of the study was the retrospective nature of the study, the small number of patients included in the study, as well as the referral bias.

The study shows us that the revised ICBD has the best power in classifying the disease. The PEDBD criteria are also having a similar power to revised ICBD and require further refinement with various population-based studies. More studies should be done to evaluate the gastrointestinal involvement in the BD patients.

Acknowledgements

We would like to thank Dr. Senthilvel Vasudevan and Dr. Jithesh K Ambujam for the help given in statistical analysis.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

[11]

References

1Jennette JC, Falk RJ, Bacon PA, Basu N, Cid MC, Ferrario F, et al. 2012 revised international chapel hill consensus conference nomenclature of vasculitides. Arthritis Rheum 2013;65:1-11.
2Davatchi F, Sadeghi Abdollahi B, Chams-Davatchi C, Shahram F, Shams H, Nadji A, et al. The saga of diagnostic/classification criteria in Behcet's disease. Int J Rheum Dis 2015;18:594-605.
3Criteria for diagnosis of Behçet's disease. International Study Group for Behçet's Disease. Lancet 1990;335:1078-80.
4Davatchi F, Assaad-Khalil S, Calamia KT, Crook JE, Sadeghi-Abdollahi B, Schirmer M, et al. The International Criteria for Behçet's Disease (ICBD): A collaborative study of 27 countries on the sensitivity and specificity of the new criteria. J Eur Acad Dermatology Venereol 2014;28:338-47.
5Koné-Paut I, Shahram F, Darce-Bello M, Cantarini L, Cimaz R, Gattorno M, et al. Consensus classification criteria for paediatric Behçet's disease from a prospective observational cohort: PEDBD. Ann Rheum Dis 2016;75:958-64.
6Zouboulis CC. Epidemiology of adamantiades-Behçet's disease. Ann Med Interne (Paris) 1999;150:488-98.
7Davatchi F, Abdollahi BS, Chams-Davatchi C, Shahram F, Nadji A, Shams H, et al. Validation of the revised international criteria for Behcet's disease (ICBD) in Iran. Clin Rheumatol 2015;34:315-20.
8Hussein MA, Ellawindi MI, Ragab G. Performance of classification criteria for Behcet's disease in an Egyptian cohort. Indian J Rheumatol 2017;12:152-5.
9Davatchi F, Abdollahi BS, Shahram F, Nadji A, Chams-davatchi C, Shams H, et al. Validation of the International Criteria for Behcet's disease (ICBD ) in Iran 2010;13:55-60.
10Davatchi F, Chams-Davatchi C, Shams H, Nadji A, Faezi T, Akhlaghi M, et al. Adult Behcet's disease in Iran: Analysis of 6075 patients. Int J Rheum Dis 2016;19:95-103.
11Batu ED, Sönmez HE, Sözeri B, Butbul Aviel Y, Bilginer Y, Özen S, et al. The performance of different classification criteria in paediatric Behçet's disease. Clin Exp Rheumatol 2017;35 Suppl 108:119-23.