J Med Cases

Journal of Medical Cases, ISSN 1923-4155 print, 1923-4163 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Med Cases and Elmer Press Inc

Journal website http://www.journalmc.org

Case Report

Volume 7, Number 8, August 2016, pages 334-340

Differentiating Rheumatoid Arthritis Related Musculoskeletal Pain in Patients With Concurrent Sickle Cell Disease: A Case Series and Literature Review

Figure 1. X-ray of right knee showing (A) erosive arthritis in the joint due to RA and (B) sclerosis in the tibial metaphysis due to SCD.

Figure 2. X-ray of left knee lateral view showing (A) erosive arthritis in the joint due to RA and (B) sclerosis in the diaphysis due to SCD.

Figure 4. X-ray of right shoulder showing (A) avascular necrosis of humeral head with preserved articular surface.

Figure 5. Right hand X-ray shows (A) erosive arthritis, subluxation at the metacarpophalangeal joints and periarticular osteopenia.

Figure 6. Comparison of biomarkers LDH and CRP in case 1 during admissions. Hospitalization for painful events due to sickle cell disease (red arrow). Hospitalization for painful events due to rheumatoid arthritis (green arrow).

**Table 1.** Baseline Characteristics of Patients at the Time of Diagnosis With RA
	Case 1	Case 2	Case 3	Case 4	Case 5	Case 6	Case 7	Case 8
Hgb: hemoglobin; HPLC: high performance liquid chromatography; Hgb S: sickle cell hemoglobin; Hgb F: fetal hemoglobin; Hgb A&A2: adult hemoglobins; ESR: erythrocyte sedimentation rate; CRP: C-reactive protein; RF: rheumatoid factor antibody; CCP IgG: cyclic citrullinated peptide antibody.
Age at diagnosis of RA	33	36	22	55	37	38	53	29
Gender	Male	Female	Female	Female	Female	Female	Female	Female
Date of diagnosis of RA	May 2010	May 2008	March 2012	April 2010	August 2003	December 2015	July 2010	August 1999
Sickle cell genotype	SS	SS	SS	SS	SS	SS	SS	SS
Hgb (mg/dL)	7.6	5.3	6.7	6.9	8	8	7.1	7.3
HPLC
Hgb S%	89	84.4	90.4	85	90.7	78.3	87.5	86.4
Hgb F%	3	9.7	2.2	6.7	3.3	12.5	2.2	7.5
Hgb A%	2	0	0	0	0	6.6	0	0
Hgb A2%	4.6	3.8	4.7	4.3	4.3	2.6	4.9	4.6
Inflammatory markers
ESR (mm/h)	96	88	140	54	115	97	45	118
CRP (mg/L)	77.9	47.6	12.39	16	1.03	2.78	1.1	3.4
Immunologic markers
RF (IU/mL)	378	263	188	610	188	81	161	124
CCP IgG (mg/L)	> 250	> 250	> 250	> 250	> 250	> 250	> 250	142

Table 1. Baseline Characteristics of Patients at the Time of Diagnosis With RA

Case 1

Case 2

Case 3

Case 4

Case 5

Case 6

Case 7

Case 8

Hgb: hemoglobin; HPLC: high performance liquid chromatography; Hgb S: sickle cell hemoglobin; Hgb F: fetal hemoglobin; Hgb A&A2: adult hemoglobins; ESR: erythrocyte sedimentation rate; CRP: C-reactive protein; RF: rheumatoid factor antibody; CCP IgG: cyclic citrullinated peptide antibody.

Age at diagnosis of RA

Gender

Male

Female

Date of diagnosis of RA

May 2010

May 2008

March 2012

April 2010

August 2003

December 2015

July 2010

August 1999

Sickle cell genotype

Hgb (mg/dL)

7.6

5.3

6.7

6.9

7.1

7.3

HPLC

Hgb S%

84.4

90.4

90.7

78.3

87.5

86.4

Hgb F%

9.7

2.2

6.7

3.3

12.5

2.2

7.5

Hgb A%

6.6

Hgb A2%

4.6

3.8

4.7

4.3

2.6

4.9

4.6

Inflammatory markers

ESR (mm/h)

140

115

118

CRP (mg/L)

77.9

47.6

12.39

1.03

2.78

1.1

3.4

Immunologic markers

RF (IU/mL)

378

263

188

610

188

161

124

CCP IgG (mg/L)

> 250

142

**Table 2.** Number of Admissions for Painful Events Before and After Diagnosis of RA
	Case 1	Case 2	Case 3	Case 4	Case 5	Case 6	Case 7	Case 8
Data only represent the available information from our institution.
Painful events requiring admission in the 5 years period before diagnosis of RA	2	1	0	0	0	9	1	0
Painful events requiring admission in the 5 years period after diagnosis of RA	53	16	2	16	2	1	4	6

Table 2. Number of Admissions for Painful Events Before and After Diagnosis of RA