Small-sized vessel vasculitis with fever, weight loss, and arthralgia

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Eiman Ghaffarpasand, M.D. [2]

Abbreviations: ABG= Arterial blood gas, ANA= Antinuclear antibody, ANP= Atrial natriuretic peptide, ASO= Antistreptolysin O antibody, BNP= Brain natriuretic peptide, CBC= Complete blood count, COPD= Chronic obstructive pulmonary disease, CRP= C-reactive protein, CT= Computed tomography, CXR= Chest X-ray, DVT= Deep vein thrombosis, ESR= Erythrocyte sedimentation rate, HRCT= High Resolution CT, IgE= Immunoglobulin E, LDH= Lactate dehydrogenase, PCWP= Pulmonary capillary wedge pressure, PCR= Polymerase chain reaction, PFT= Pulmonary function test.

Diseases			Clinical manifestations								Para-clinical findings									Gold standard	Additional findings
			Symptoms					Physical examination
											Lab Findings				Imaging				Histopathology
			Headache	Fever	Weight loss	Arthralgia	Claudication	Bruit	HTN	Focal neurological disorder	Biomarker	CBC	ESR	Other	CT scan	Angiography	Ultrasound/ Echocardiography	Other
Small-Vessel Vasculitis	Immune complex small-vessel vasculitis	Hepatitis C virus-associated cryoglobulinemic vasculitis	+/-	+/-	+	+	-	-	+	+/-	HCV RNA, Cryoglobulins	Leukocytosis, Anemia	↑	↓Serum C4, Positive RF	Increased hepatic echogenicity	-	Hepatomegaly, Splenomegaly	Increased hepatic echogenicity in MRI	Vasculitic skin, Antigen infilteration in lesions	HCV RNA, Histological confirmation	Palpable purpura, Microscopic hematuria
	Hematologic disease	Chronic Lymphocytic Leukemia (CLL)	+	+	+	+	+/-	-	-	+/-	CD5, CD19, CD20, IgVH	Absolute lymphocytosis, Smudge cells	↑	Flow cytometry	Staging	-	-	-	Large atypical cells, cleaved cells, and prolymphocytes	Chromosomal and genetic testing	Easy bruising
		Non-Hodgkin Lymphoma	+	+	+	+	+/-	+/-	+/-	+/-	MYC, BCL2, BCL6, and TP53	Lymphocytosis, Anemia, Thrombocytopenia	↑	↑Lactate dehydrogenase (LDH), Hypercalcemia	Enlarged lymph nodes, Hepatosplenomegaly, Filling defects in the liver and spleen	-	Hepatosplenomegaly	Mediastinal lymphadenopathy	Small cleaved or noncleaved, intermediate, or large cell with a follicular or diffuse pattern	Surgically excised tissue biopsy	Easy bruising, Testicular mass, Skin lesion
	Systemic disease	Sarcoidosis	+	+	+	+	-	-	-	+/-	IL-2 and IFN-γ	Mild anemia	↑	↑ACE, ↑1, 25-dihydroxyvitamin D	Active alveolitis or fibrosis	-	Hepatosplenomegaly	Bilateral hilar adenopathy	Noncaseating granulomas (NCGs)	Histological confirmation	Heart block, Ocular lesion
		Legionella Infection	+	+	+	+	-	-	-	+/-	Inflammatory cytokines	Leukocytosis with left shift, Thrombocytosis	↑	↑D-dimer, FDP, Hyponatremia	Pleural effusion	-	-	Nonspecific and indistinguishable CXR	Intra-alveolar inflammation, Microabscesses in the parenchyma	Sputum culture	Cough, Diarrhea
		Systemic lupus erythematosus	+	+	+	+	-	-	+	+	Anti dsDNA, ANA	Leukopenia, Lymphopenia, Anemia, Thrombocytopenia	↑	↑Cr or BUN, ↑ALT or AST, Proteinuria	Interstitial lung disease, Pneumonitis, Pulmonary emboli, Alveolar hemorrhage	Aneurysms	Pericardial effusion, pulmonary hypertension, or verrucous Libman-Sacks endocarditis in echocardiography	Central nervous system (CNS) lupus white-matter changes in MRI	Staging lupus nephritis	Anti-dsDNA antibody test	Skin rashes or photosensitivity
		Relapsing polychondritis	-	+/-	+/-	+	+	-	-	-	-	Leukocytosis, Anemia	-	Cryoglobulins, ANA, C-ANCA	Calcification of cartilaginous structures	Aortic root dilatation	Aortic root dilatation and degree of aortic regurgitation in echocardiography	Tracheal stenosis in CXR	Chondrolysis, Chondritis, Perichondritis	Clinical findings coupled with imaging	Ear pain and redness, Polyarthritis