Rheum Mimics: Dermatologic Conditions 2% Flashcards
What is the differential diagnosis of erythema nodosum?
Idiopathic - > 50%
Infection: Strep (ASO, DNase B), TB (Quant Gold or PPD)
Drug-induced
IBD
Sarcoid
Reactive arthritis
Cutaneous PAN – usually periarticular, can be larger in diameter
What skin lesion typically occurs in school-aged children with no underlying evidence of arthritis or systemic disease. They are most commonly found on the lower extremities, but they may also occur in the upper extremities or scalp. Clinical history and laboratory evaluation findings are often unremarkable. They typically regress without treatment, and excision is only recommended if the location causes distress to the patient.
Benign rheumatoid nodules
What skin lesion has the following histology?
a central area of necrosis surrounded by palisading macrophages and lymphocytes
Rheumatoid nodule
Histopathologic features of a typical rheumatoid nodule consists of 3 distinct zones. There is a central area of fibrinoid necrosis and granulation tissue surrounded by a radially arranged palisade of connective tissue cells and then enveloped by chronic lymphocytic infiltrate. The palisading layer consists primarily of macrophages, while the lymphocytic infiltrate primarily consists of T cells. B cells and plasma cells are rare, and there are no mucin deposits.
Can be benign rheumatoid nodule in healthy school age kid most commonly found on the lower extremities, but they may also occur in the upper extremities or scalp.
Or 30% of patients with rheumatoid factor-positive polyarthritis (children and adults) may develop concurrent rheumatoid nodules, indicating a worse prognosis. These rheumatoid nodules are located on bony prominences and pressure points (olecranon, flexor tendon sheaths, Achilles tendon, and soles of feet) and are often associated with destructive arthritis and increased extra-articular manifestations.
What skin lesion has the following histology?
lymphohistiocytic infiltrate with central degeneration of collagen and mucin deposition
granuloma annulare
similar to rheumatoid nodule except has mucin
The histopathology of granuloma annulare may be somewhat indistinguishable from that of a rheumatoid nodule. As such, some investigators have proposed that benign rheumatoid nodules and deep granuloma annulare may be, in fact, similar entities. Both conditions are characterized by a central area of collagen degeneration and necrosis surrounded by a lymphohistiocytic infiltrate. Granuloma annulare may have an interstitial or palisading pattern. In contrast to rheumatoid nodules, granuloma annulare commonly contains mucin deposits. Localized granuloma annulare typically presents with an asymptomatic, erythematous, annular, nonscaly plaque with central clearing. Borders are typically firm and raised and described as a “rope-like” rim.
What skin lesion has the following histology?
noncaseating granuloma surrounded by sparse lymphocytic infiltrates
Cutaneous sarcoidosis
Cutaneous sarcoidosis may present as flesh-colored papules or erythematous annular plaques. Histopathology of these lesions typically reveals “naked granulomas”. These granulomas consist of histiocytes, giant cells, and macrophages surrounded by sparse lymphocytic infiltrates. The term naked granulomas in part refers to the absence of dense surrounding inflammatory infiltrates (as would be seen in cutaneous tuberculosis)
What skin lesion has the following histology?
Lobular panniculitis with lymphohistiocytic infiltrate
erythema nodosum
What skin lesion has the following histology?
Perivascular infiltration of lymphocytes, plasma cells, and histiocytes
erythema migrans of Borrelia infection, Lyme disease (silver stain shows rare spirochetes)
What skin lesion has the following histology?
Epidermal thickening, hyperkeratosis, and chronic inflammatory infiltrate of mainly lymphocytes
psoriasis
What skin lesion has the following histology?
perivascular infiltrate of lymphocytes (rare plasma cells and eosinophils) and thickened collagen bundles in the subcutaneous tissue
Localized scleroderma
What disease has mouth ulcers described as typically minor or herpetiform, last 3 to 10 days, and heal without scarring?
Behçet disease
What disease has mouth ulcers described as large painful lesions that may take up to 4 to 6 weeks to resolve and may result in scarring
Complex aphthosis
Complex aphthosis should be considered in an otherwise healthy patient who has persistent oral aphthae or recurrent oral and genital aphthae and in whom Behçet disease has been excluded.
Patients with complex aphthosis tend to have large painful lesions that may take up to 4 to 6 weeks to resolve and may result in scarring
What disease involves, aortitis or thoracic aortic aneurysm, mouth and genital ulcers,, and inflamed cartilage?
(MAGIC) syndrome
Mouth and genital ulcers with inflamed cartilage
an overlap syndrome of relapsing polychondritis and Behçet disease.
