Exploration of Immunology

From: Diagnostic performance and cutoff optimisation of the CTD Screen assay for ANA detection compared with HEp-2 IFA

Table 1. Patient characteristics.

Total number		N = 347
Age		Range = 1–81 years Median = 40 years IQR = 30–51.5 years
Male: Female ratio		1:5.8
Clinical features
Primary diagnosis		Systems involved
SLE SjS MCTD LSSc DSSc UCTD Dermatomyositis Non-SARDs conditions	36.0% 17.6% 14.9% 11.7% 5.4% 2.7% 0.3% 30%	Musculoskeletal Dermatological Cardiovascular Auditory/ocular Febrile illness Respiratory Endocrine Gastrointestinal/liver Hematological Renal Central nervous system Gynaecological system	62.0% 47.0% 22.7% 21.8% 21.8% 20.0% 17.6% 16.1% 13.9% 9.4% 8.8% 7.3%
Laboratory findings (median values)
Hemoglobin Anemia -Normocytic normochromic -Microcytic normochromic -Macrocytic Leucocyte count -Leucocytosis -Leukopenia Platelet count -Thrombocytosis -Thrombocytopenia ESR -Raised C-reactive protein -Raised	11.3 g/dL 56% 74.5% 23.5% 2.0% 6.8 × 10⁹/L 3.6% 3.3% 224 × 10⁹/L 22% 3.9% 36.5 mm/h 87.8% 7 mg/L 80%	Blood urea Uric acid Serum creatinine AST ALT ALP GGT Total bilirubin Conjugated bilirubin Total protein Albumin C3 (median) C4 (median) LDH	24 mg/dL 5.2 mg/dL 0.6 mg/dL 25 IU/L 27 IU/L 88 IU/L 148 IU/L 0.8 mg/dL 0.2 mg/dL 7.6 g/dL 3.8 g/dL 124 mg/dL 22 mg/dL 293 U/L

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ALP: alkaline phosphatase; ALT: alanine aminotransferase; AST: aspartate aminotransferase; DSSc: diffuse systemic sclerosis; GGT: gamma-glutamyl transferase; IQR: inter-quartile range; LDH: lactate dehydrogenase; LSSc: limited systemic sclerosis; MCTD: mixed connective tissue disease; SARDs: systemic autoimmune rheumatic diseases; SjS: Sjogren’s syndrome; SLE: systemic lupus erythematosus; UCTD: undifferentiated connective tissue disease.

Declarations

Author contributions

AK: Investigation, Writing—original draft. VD and SKS: Data curation. RWM: Supervision. MK and SC: Formal analysis. YK: Conceptualization, Methodology, Resources, Data curation, Supervision, Writing—original draft, Writing—review & editing. All authors read and approved the submitted version.

Conflicts of interest

The authors declare that they have no conflicts of interest.

Ethical approval

The Institutional Ethics Committee approved this study (Approval No. INT/IEC/2022/SPL-1051).

Consent to participate

A prior written informed consent form was obtained from the parents/guardians of each subject.

Consent to publication

Not applicable.

Availability of data and materials

The datasets supporting the findings of this study are available from the corresponding author upon reasonable request.

Funding

This work was partly supported by Thermo Fisher Scientific, which provided select consumables required for the CTD Screen test. Their contribution is sincerely appreciated. The funder(s) had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Copyright

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Open Exploration maintains a neutral stance on jurisdictional claims in published institutional affiliations and maps. All opinions expressed in this article are the personal views of the author(s) and do not represent the stance of the editorial team or the publisher.

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