CASE #1: Leukocytoclastic vasculitis
Leukocytoclastic vasculitis is characterized by inflammation directed at small blood vessels in the skin. The process is mediated by neutrophils. Histologically, leukocytoclasis (i.e., destruction of neutrophils leaving nuclear debris) can be seen.1,2,3 When blood vessel inflammation occurs, vessel wall destruction can take place, which may lead to hemorrhage, ischemia, and/or infarction.2
Leukocytoclastic vasculitis may be the result of an idiopathic or primary process. Henoch-Schonlein purpura is an idiopathic syndrome associated with a cutaneous vasculitis as well as arthralgias and vasculitis in the renal and GI systems.2 Leukocytoclastic vasculitis may also result from a secondary process associated with another systemic disease, such as infection, collagen vascular disease (particularly systemic lupus erythematosus and rheumatoid arthritis), cryoglobulinemia, or, occasionally, lymphoma and myeloma. It is important to be vigilant about noticing the signs and symptoms of systemic disease in a patient presenting with a cutaneous vasculitis. Although it is uncommon, recent drug ingestion is another possible etiology of leukocytoclastic vasculitis. The drugs most frequently associated include antibiotics (i.e., penicillin, sulfonamides, chloramphenicol, and streptomycin), aspirin, phenothiazine, and thiazides.
Clinically, leukocytoclastic vasculitis most often presents with palpable purpura, especially on the lower extremities.2 Other less common presentations include nonpalpable purpura, infiltrated erythema, ulcers, livedo reticularis, and nodules. Vasculitis that is restricted to the skin is often referred to as cutaneous leukocytoclastic angiitis or hypersensitivity vasculitis. Symptoms of a systemic involvement may include hematuria, arthritis, fever, abdominal pain, melena, cough, hemoptysis, headaches, and peripheral neuropathy. The kidney is the most frequently involved internal organ, with some studies showing up to half of patients presenting with leukocytoclastic vasculitis having renal involvement. Although chronic cutaneous disease may involve ulceration or painful bouts of purpura, serious complications of leukocytoclastic vasculitis are most often associated with internal organ involvement. When a patient with vasculitis presents, it is imperative to rule out systemic disease.
Skin biopsy is the gold standard for diagnosing this condition. The biopsy should be taken from the earliest purpuric or symptomatic lesion to obtain the most accurate findings. If the biopsy is poorly timed, the pathological features of vasculitis may be absent. This has to be considered in the interpretation of a negative biopsy from a patient whose clinical findings suggest a cutaneous vasculitis. The diagnosis of leukocytoclastic vasculitis can be confidently made when the inflammation directed at small blood vessels in the skin is accompanied by fibrinoid necrosis. Endothelial cell swelling is a sign of endothelial damage. Vascular damage can be inferred with the extravasation of RBCs (purpura) and necrosis (infarct); however, these two findings are supportive rather than diagnostic (they are also seen in other disorders).
Direct immunofluorescence stains are helpful in diagnosing Henoch-Schonlein purpura, in which the immunoglobulin (Ig) deposition is IgA. Henoch-Schonlein purpura is essentially a leukocytoclastic vasculitis accompanied by IgA immune complexes within affected organs. In adults, confirmation of the diagnosis by biopsy and direct immunofluorescence is important, as Henoch-Schonlein purpura is not common in this patient pouplation. However, in children, biopsy is reserved for patients with an unusual presentation or those with significant renal disease
To rule out sepsis, blood cultures should be obtained in all patients presenting with a cutaneous vasculitis and fever. If sepsis is suspected as an underlying etiology for leukocytoclastic vasculitis, it is important to keep disseminated intravascular coagulation (DIC) in the differential diagnosis. In DIC, purpuric lesions may be elevated because of edema that acutely accompanies necrosis. Typically, patients with DIC will have moderate to severe thrombocytopenia. Diagnosis can be confirmed by demonstrating decreased fibrinogen and increased fibrinolysis (e.g., elevated fibrin degradation products and elevated D-dimer).
If no obvious etiology is apparent, patients with a cutaneous vasculitis should undergo such serologic studies as antinuclear antibody, antineutrophil cytoplasmic antibody, rheumatoid factor, serum protein electrophoresis, cryoglobulins, and hepatitis-associated antigen.
If an underlying systemic disorder can be identified, the treatment of this underlying disease may result in clearing of the cutaneous vasculitis. Similarly, if drug ingestion or infection is the suspected etiology, withdrawal of the drug or treatment of the infection may simultaneously treat the leukocytoclastic vasculitis. In patients without systemic involvement, conservative treatment usually leads to good results. Leukocytoclastic vasculitis often affects dependent areas, so elevating the legs or wearing support hose may be useful. Therapy with antihistamines, aspirin, or nonsteroidal anti-inflammatory drugs can be used. More extensive therapy is indicated for recurrent or persistent skin disease. For mild chronic disease, colchicine and dapsone are first-line agents. Severe cutaneous disease requires more potent immunosuppression. If the leukocytoclastic vasculitis is refractory, plasmapheresis and IV Ig are possible considerations.
Leukocytoclastic vasculitis is an uncommon disorder. The annual incidence of biopsy-proven cutaneous vasculitis ranges in studies from 39.6 to 59.8 per million. Although leukocytoclastic vasculitis may affect anyone, it is slightly more prevalent in females. The condition is also more prevalent in adults. When children are affected, it is most commonly Henoch-Schonlein purpura.
In this case, the cefazolin was stopped, and the patient was transitioned to oral azithromycin 500 mg/day and discharged. The rash resolved altogether over the course of several weeks.