Clinical Utility and Cost Effectiveness of Complement 3 and Complement 4 in Different Clinical Subspecialties in Hamad Medical Corporation

Abstract

Background: Complement system is one of ancient innate immune system in our body fighting against pathogens and foreign bodies. It is activated by either one of its three pathways, classical, alternative or lectin. Because of its role and importance in combating against different pathological conditions, it works through defined proteins including regulators and inhibitors. However, over or under stimulation of complement system can lead to various diseases. A number of analytical assays are used to measure complement proteins and its activation states considering complement 3 (C3), complement 4 (C4) as the most common test used. Objectives: Our aims are to study the clinical utility and cost effectiveness of C3 and C4 among different clinical subspecialties in Hamad Medical Corporation (HMC), Doha-Qatar. Design and Methods: A retrospective study was conducted using electronic medical records to generate patient's list from clinical immunology laboratory at HMC. Data on 326 patients were collected from 1st January till 31st March, 2017 and used as pilot study after omitting duplications. The data was studied for its demographical, disease categories, C3 and C4 test results. C3 and C4 test cost were calculated inside HMC and compared to other healthcare providers in country and abroad. Results: A total of 326 patients, 148 males and 178 females (M/F ratio:0.8:1), of age (mean age +-SD) of 36 +-17.6 years. 289(86%) were >15 years and 47(14%) were 15 or less. Kidney diseases (34%), autoimmune diseases (25%), and allergic diseases (18%) were the top 3 diseases, and constituted 77% of all diseases. 45/336 (13.4%) showed low C3, C4, or both. Mean levels of C3(+- SD) was 120.8 +- 36.3 mg/dl, and C4 was27.85-11.9 mg/dl. High C3 and C4 levels were observed in 53 (15.7%) of patients. The cost of performing one test either C3 or C4 in HMC is 22 QR ($6), while other healthcare providers inside the country costed 150-300 QR ($41.2-$82.4). Conclusions: Autoimmune diseases, renal diseases and joist diseases were the most common diseases with low C3 and C4 levels. Although the cost of a single test of C3 or C4 is low, the total annual cost is huge. The treating physician is recommended to exercise judicious clinical wisdom when ordering C3 or C4 tests as diagnostic tools