Table 2 : Clinical characteristics of chronic hepatitis C (CHC) patients with possible and pure
red cell aplasia (PRCA) identified by a claims-based algorithm*.

N (%) unless otherwise specified Possible PRCA* Adjudicated Not Adjudicated
N (%) N (%) N (%)
Total 25 -- 17 -- 8 --

Age, years, mean±SD 51.6 ±18.1 47.9 ±20.2 59.3 ±9.8
Gender, female 11 (44.0) 6 (35.3) 5 (62.5)

Probable PRCA definition

Any of the below criteria 21 (84.0) 15 (88.2) 6 (75.0)
≥1 medical claim for chest CT scan 8 (32.0) 6 (35.3) 2 (25.0)
≥1 medical claim for RBC transfusion 14 (56.0) 10 (58.8) 4 (50.0)
≥1 pharmacy claim for the initiation of
a new immunosuppressive therapy
11 (44.0) 8 (47.1) 3 (37.5)

Physician specialty on the first diagnosis of PRCA

Emergency medicine 2 (8.0) 1 (5.9) 1 (12.5)
Hematology or oncology 10 (40.0) 8 (47.1) 2 (25.0)
Internal medicine 6 (24.0) 3 (17.6) 3 (37.5)
Other (non-physician) 3 (12.0) 2 (11.8) 1 (12.5)
Pediatrics (all types) 1 (4.0) 1 (5.9) -- (0.0)
Not specified 3 (12.0) 2 (11.8) 1 (12.5)

Co-medication use in the 60 days prior to PRCA diagnosis

Erythropoietin (EPO) in the three
months prior to PRCA diagnosis
9 (36.0) 5 (29.4) 4 (50.0)
Anti-epileptic medications 2 (8.0) 2 (11.8) -- (0.0)
Azathioprine -- (0.0) -- (0.0) -- (0.0)
Chloraphenicol -- (0.0) -- (0.0) -- (0.0)
Immunosuppressive therapy 10 (40.0) 8 (47.1) 2 (25.0)
Sulfonamides 4 (16.0) 4 (23.5) -- (0.0)
Isoniazid -- (0.0) -- (0.0) -- (0.0)
Procainamide -- (0.0) -- (0.0) -- (0.0)

CHC: Chronic hepatitis C; CT: Computed tomography; EPO: Erythropoietin; ICD-9-CM: International
Classification of Diseases, Ninth Revision, Clinical Modification; PRCA: Pure red cell aplasia; RBC: Red blood
cell; SD: Standard deviation
*Possible PRCA cases from claims data are patients with any medically-attended claim for aplastic anemia
(ICD-9-CM 284.8x or 284.9x) and any medical claim for a bone marrow biopsy in the 30 days prior to and
including the date of the claim for aplastic anemia.
No medical record received or received medical records that did not contain the required key elements
(i.e., bone marrow biopsy result and complete blood count report) for adjudication.

Quinlan et al.Epidemiology Reports  2015 3:1DOI : 10.7243/2054-9911-3-1