Clinical, radiological, and biochemical characteristics in patients with diseases mimicking polymyalgia rheumatica

Figures & data

Table 1 Age, serum CRP, MMP-3, VEGF levels before and after the treatment in patients with PMR, pseudogout, RS3PE syndrome, and post-infectious polyarthritis

Case	Diagnosis	Age		CRP (mg/dl)	MMP-3 (ng/ml)	VEGF (pg/ml)
	PMR (n = 7)	78.1 ± 8.2	Before	11.4 ± 4.8	189.0 ± 91.4	1,114.2 ± 297.4
			After	1.5 ± 1.0*	286.9 ± 204.0	565.1 ± 182.3*
A	Pseudogout	83	Before	24.3	252.0	1,190
			After	1.2	117.0	894
B	RS3PE syndrome	65	Before	17.8	729.0	1,650
			After	8.5	328.0	1070
C	Post-infectious polyarthritis	89	Before	12.1	238.0	805
			After	1.3	70.1	450

Notes: Cases A–C corresponds to A–C in Figure 1, respectively. Values in PMR patients indicate mean ± SD.

* P < 0.05 vs values before the treatment by Wilcoxon’s signed rank test. Normal range of CRP, MMP-3, and VEGF levels is <0.3 mg/dl, <115 ng/ml, and 17.3–59.7 pg/ml, respectively.

Abbreviations: CRP, C-reactive protein; MMP-3, matrix metalloproteinase-3; PMR, polymyalgia rheumatica; RS3PE, remitting seronegative symmetrical synovitis with pitting edema.

Table 2 Changes in serum CRP levels after one week’s treatment using NSAIDs in patients with PMR, pseudogout, RS3PE syndrome, and post-infectious polyarthritis

Case	Diagnosis		CRP (mg/dl)	%Changes of serum CRP levels
	PMR (n = 7)	Before	10.4 ± 4.4	−7.2%
		After one week	9.1 ± 3.4#
A	Pseudogout	Before	24.3	−95.1%
		After one week	1.2
B	RS3PE syndrome	Before	20.8	−22.1%
		After one week	16.2
C	Post-infectious polyarthritis	Before	12.1	−89.3%
		After one week	1.3

Notes: Case A–C corresponds to A–C in Figure 1, respectively. Values in PMR patients indicate mean ± SD.

# Indicates no significant differences vs values before treatment by Wilcoxon’s signed rank test.

Abbreviations: CRP, C-reactive protein; MMP-3, matrix metalloproteinase-3; PMR, polymya rheumatica; RS3PE, remitting seronegative symmetrical synovitis with pitting edema.

Figure 1 Gallium-67 scintigraphic findings of patients with polymyalgia rheumatica (P), pseudogout A), remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome B), and post-infectious polyarthritis C). A–C corresponds to case A–C in Table 1, respectively. Arrows indicate a gallium uptake. Dotted arrows indicate a gallium uptake in metacarpophalangeal joints in a patient in RS3PE syndrome.

Figure 2 The radiographs of the patient with pseudogout demonstrated chondrocalcinosis (arrows) on the wrist A), knee B), and hip C).

Table 3 Clinical and biochemical characteristics for polymyalgia rheumatic

Age ≥ 50 years

Elevated serum CRP, MMP-3, and VEGF levels

Symmetrical gallium-67 uptake in shoulders and/or pelvic girdle

A bad response to NSAIDs

A rapid response to steroid

No abnormalities in the radiographs of joints

Abbreviations: CRP, C-reactive protein; MMP-3, matrix metalloproteinase-3; NSAIDs, nonsteroidal anti-inflammatory drugs.