The incidence and prevalence of WCD in the United States is unknown, but it is classified as a rare disease. Women in their 30s-70s account for the majority (75%) of cases, and it is rare in pediatric populations.
WCD is chronic, marked by episodes of exacerbation and remission. It begins with acute onset of fever and malaise and the appearance of painful subcutaneous nodules. These nodules typically resolve over a period of weeks to months. Prognosis varies widely depending on the level of systemic involvement. In addition to involving the skin, WCD can affect lungs, heart, intestines, adrenal glands, kidney, spleen, and orbits. If there is only skin involvement, there will be a waxing and waning of lesions, and prognosis is relatively good. However, there may be significant morbidity and up to 10% mortality in patients with severe visceral involvement. It is worth reiterating that since many prior cases of WCD have at this point been reclassified as alternate entities, the true morbidity and mortality of this controversial entity is difficult to evaluate.
Signs – Recurrent, symmetric subcutaneous nodules. The lower extremities are sites of predilection.
Symptoms – Malaise, fever, fatigue, arthralgias, myalgias, nausea, vomiting, bone pain, abdominal pain, and weight loss may occur.
M35.6 – Relapsing panniculitis [Weber-Christian]
33760009 – Relapsing febrile nodular nonsuppurative panniculitis
- Alpha-1 antitrypsin deficiency panniculitis – Check patient's alpha-1 antitrypsin levels, pulmonary findings, and family history.
- Pancreatic panniculitis – Check patient's amylase and lipase levels; evaluate for distinct histologic features ("ghost" adipocytes and areas of calcification within the altered fat).
- Histiocytic cytophagic panniculitis
- Polyarteritis nodosa – Biopsy demonstrating a medium vessel vasculitis, sometimes with ANCA serologic positivity.
- Physical panniculitis includes trauma-induced, cold-induced, and self-induced (factitial). Often a history of trauma and/or surrounding ecchymoses will be present, with lesions limited to exposed areas.
- Systemic lupus erythematosus – Test patient for ANA, anti-dsDNA, and anti-Sm antibodies.
- Systemic sclerosis – Look for supportive physical exam findings and serologies, including potential anti-SCL 70, anti-centromere, anti-RNA polymerase I or II antibodies.
- Erythema nodosum – Nonulcerating nodules, often symmetrical on the anterior shins, and usually with a clear trigger or associated underlying disease or systemic illness.
- Nodular vasculitis / erythema induratum – A history of tuberculosis infection coupled with a panniculitis on the posterior calves and supportive histologic findings on biopsy.
- Panniculitic T-cell lymphoma – Look for atypical cells on biopsy specimen.
- Lupus panniculitis – Patients will often have other features of lupus, and the involved panniculus may demonstrate overlying features of chronic cutaneous lupus.
- Suppurative / chronic infections – Nocardia, Actinomyces, MRSA, Leishmania (Old World, New World leishmaniasis), atypical mycobacterial, and other chronic skin infections can present with skin nodules which sometimes ulcerate and express liquid material; biopsies and tissue cultures can help distinguish between skin infections and WCD.