Cryoglobulinemic vasculitis is an immune-complex-mediated small-vessel vasculitis characterized by complement activation and endothelial injury. Its clinical manifestations are heterogeneous and may range from limited cutaneous involvement to systemic disease. We report the case of a 65-year-old woman who developed a symmetrical violaceous dermatosis involving the upper and lower extremities, accompanied by arthralgias and distal paresthesias. Laboratory investigations revealed marked hypocomplementemia and positive circulating cryoglobulins. Histopathological examination of a skin biopsy demonstrated leukocytoclastic vasculitis, leading to the diagnosis of idiopathic cryoglobulinemic vasculitis after exclusion of hepatitis C virus infection, autoimmune diseases, and associated hematologic malignancies, with no evidence of major systemic organ involvement. Treatment with corticosteroid- and cyclophosphamide-based immunosuppression achieved sustained disease control, resulting in approximately 90% symptomatic improvement. This case highlights the importance of recognizing cardinal manifestations, such as palpable purpura, arthralgias, and hypocomplementemia, when evaluating patients with suspected cryoglobulinemic vasculitis, even in the absence of identifiable secondary causes. Early recognition, histopathological confirmation, and a multidisciplinary approach are essential for establishing an accurate diagnosis and implementing timely therapeutic intervention aimed at preventing disease progression and irreversible organ damage.

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis characterized by asthma, eosinophilia, and multi-organ involvement. Adolescent-onset disease is uncommon, and evidence guiding biologic therapy in this population remains limited. We report the case of an 18-year-old female with a history of chronic rhinosinusitis and eosinophilic asthma who presented with worsening asthma control, arthralgia, and peripheral eosinophilia (4, 600 cells/μL), with palpable purpura developing during hospitalization. Chest radiography was initially unremarkable, but chest computed tomography revealed peripheral ground-glass opacities and consolidations. Further workup demonstrated eosinophil-rich perivascular infiltrates with karyorrhectic debris without necrotizing vasculitis on skin biopsy, and high-titer anti-myeloperoxidase (anti-MPO) antibodies >200 RU/mL on immunologic testing. The diagnosis of EGPA was established according to the 2022 ACR/EULAR classification criteria with a total score of 10. Initial treatment with high-dose corticosteroids resulted in partial improvement, but the disease relapsed during tapering, indicating corticosteroid dependence. Benralizumab was subsequently introduced, leading to rapid eosinophil depletion, improved pulmonary function, successful corticosteroid reduction, and prompt clinical remission. At 12-month follow-up, the patient remained in complete remission, with normalized pulmonary function, no evidence of new organ involvement, and a marked decline in anti-MPO antibody titers. This case highlights the importance of considering EGPA in adolescents presenting with difficult-to-control eosinophilic asthma and systemic manifestations, and demonstrates that benralizumab can achieve stable, long-term remission with successful corticosteroid reduction even in ANCA-positive disease.

Urticaria multiforme (UM) is a benign hypersensitivity reaction of early childhood characterized by transient annular urticarial plaques with dusky centers and acral edema. Although self-limited, UM is frequently misdiagnosed as serum sickness-like reaction (SSLR), erythema multiforme (EM), or urticarial vasculitis due to overlapping features such as fever, edema, and inflammatory laboratory abnormalities. Diagnostic uncertainty may therefore lead to extensive investigations, hospitalization, and unnecessary systemic corticosteroid therapy. A three-year-old male with a history of atopic dermatitis presented with decreased oral intake, lethargy, fever, and intermittent erythematous wheals associated with swelling of the feet and extremities. Initial evaluation revealed influenza A (H3) infection, thrombocytosis, and mildly elevated C-reactive protein. Extensive diagnostic evaluation, including multiple imaging studies and laboratory investigations, was largely unremarkable except for preserved complement levels. Due to concern for a serum sickness-like reaction, systemic corticosteroids were initiated. The dermatology consultation subsequently favored urticaria multiforme based on the transient nature of lesions lasting less than 24 hours, absence of mucosal involvement or palpable purpura, preserved complement levels, and progressive clinical improvement. The patient was managed with antihistamines and supportive care, with complete resolution of fever, edema, and urticarial lesions prior to discharge after a hospital course of six days. This case highlights influenza-associated urticaria multiforme presenting with fever and mild inflammatory marker elevation, closely mimicking immune complex-mediated disease. Recognition of lesion duration, morphology, and complement preservation is essential for accurate diagnosis and to prevent unnecessary immunosuppressive therapy.

Immunoglobulin A (IgA) vasculitis is a systemic small-vessel vasculitis with frequent gastrointestinal involvement; however, isolated terminal ileitis mimicking Crohn's disease is rare in adults. We report a case of a previously healthy adult patient who presented with acute abdominal pain and bloody diarrhea, with imaging and endoscopic findings suggestive of Crohn's disease. Colonoscopy revealed isolated terminal ileitis with a distinctive purplish cyanotic appearance. The development of palpable purpura and biopsies demonstrating IgA deposition in the skin and ileal tissue confirmed the diagnosis of IgA vasculitis. Recognition of characteristic endoscopic vascular features is critical to avoid misdiagnosis and inappropriate biological therapy.

The relationship between antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and solid malignancies is uncommon and poses significant diagnostic challenges, particularly in individuals with underlying immune dysregulation, such as human immunodeficiency virus (HIV) infection. A 61-year-old man with well-controlled HIV infection presented with nephritic syndrome and palpable purpura. Laboratory evaluation revealed active urinary sediment and positive myeloperoxidase (MPO)-ANCA. Alternative causes of vasculitis were reasonably excluded based on clinical, serological, and histopathological evaluation. Skin biopsy demonstrated leukocytoclastic vasculitis, while renal biopsy showed pauci-immune necrotizing glomerulonephritis. During hospitalization, the patient developed hematochezia, for which a colonoscopy was performed, and a mass was identified in the ascending colon. Histopathological analysis confirmed stage IIIA colorectal adenocarcinoma. Treatment included glucocorticoids, plasmapheresis, and azathioprine, followed by right hemicolectomy and adjuvant CAPEOX chemotherapy. Partial improvement in the cutaneous lesions and glomerular filtration rate was observed following vasculitis-directed therapy, the patient achieved complete resolution of both the renal and cutaneous manifestations only after right hemicolectomy and adjuvant CAPEOX chemotherapy. This case is consistent with a possible paraneoplastic link between MPO-AAV and colorectal adenocarcinoma. In patients with HIV infection, distinguishing true vasculitis from incidental autoantibody positivity is challenging. The temporal relationship and improvement with cancer-directed therapy raise the possibility that malignancy may act as a trigger for clinically overt vasculitis. Recognition of this relationship may help guide appropriate management and avoid unnecessary or prolonged immunosuppression.

IgA vasculitis (IgAV), previously known as Henoch-Schönlein purpura, is a small-vessel vasculitis that may involve the skin, joints, gastrointestinal tract, and kidneys. While purpura is a key clinical feature, presentations without rash at onset can occur and may lead to diagnostic uncertainty. We report the case of a two-year-old boy who presented with a three-day history of acute right knee pain, swelling, and reduced weight-bearing ability following a recent febrile respiratory illness. Ultrasound of the knee demonstrated mild periarticular fluid, and a provisional diagnosis of transient synovitis was made. No rash or systemic features were present at initial presentation. Two days later, the child developed a progressive rash over the lower limbs with erythematous lesions and evolving purpuric features, along with right elbow swelling and intermittent abdominal pain. These findings prompted further evaluation and led to a clinicoradiological diagnosis of IgAV. Abdominal ultrasound excluded intussusception and demonstrated mesenteric lymphadenitis. Laboratory investigations showed mild inflammatory changes and reactive thrombocytosis, while renal function and serial urinalysis remained normal. The patient was managed conservatively with close monitoring and safety-netting, without corticosteroid therapy. Symptoms gradually resolved, and no renal involvement was identified during follow-up. This case highlights an atypical presentation of IgAV in which isolated monoarthritis preceded the development of purpura, emphasizing the importance of diagnostic vigilance and serial clinical reassessment.

Levofloxacin and other fluoroquinolones are widely used antibiotics, though they can cause rare immune-mediated adverse events. We report a man in his late 50 s with long-standing type 2 diabetes mellitus and a new plantar foot wound who was prescribed oral levofloxacin for presumed soft-tissue infection. Within 48-72 h of starting levofloxacin, he developed rapidly progressive palpable purpura that began on the upper extremities and spread to the lower extremities up to the thighs, with intense pruritus, migratory arthralgias, and bullous lesions on the distal lower extremities and right upper extremity. He had no mucosal involvement and no pulmonary or gastrointestinal symptoms. Dermatologic evaluation favored small-vessel vasculitis; systemic corticosteroids were initiated and the patient was transferred for further management. Skin biopsy demonstrated leukocytoclastic vasculitis with leukocytoclasis and fibrinoid necrosis of superficial dermal vessels. Direct immunofluorescence showed perivascular IgG and C3 without IgA deposition. Workup revealed elevated inflammatory markers, elevated serum IgA, positive p-ANCA with negative MPO and PR3, probable mixed cryoglobulins, and mild hematuria and proteinuria without casts; nephrology assessed low likelihood of clinically significant renal vasculitis. Levofloxacin was discontinued and a short corticosteroid taper was completed, with steady improvement of rash and stable renal function. This case highlights the recognition and evaluation of suspected fluoroquinolone-associated cutaneous small-vessel vasculitis and the importance of early biopsy of fresh lesions when IgA vasculitis is considered.

Evans syndrome (ES) is a rare autoimmune disorder characterized by autoimmune hemolytic anemia and immune thrombocytopenic purpura, conferring an increased risk of postoperative bleeding, thrombosis, and infection. Limited guidance for perioperative management is available for patients with ES undergoing free flap reconstruction.

We report the case of an 87-year-old woman whose initial presentation was palpable purpura. Henoch-Schönlein purpura was initially diagnosed, for which she received intravenous methylprednisolone and epinastine, resulting in complete remission of the skin lesions. After discontinuation of corticosteroid therapy, she experienced multiple relapses over the ensuing months with an incomplete response to medical treatment. Metastatic breast cancer was diagnosed 7 months later, which retrospectively suggested a paraneoplastic etiology for the vasculitis. Although the association between cutaneous vasculitis and malignancy-particularly hematologic cancers-is well documented, the underlying mechanisms remain poorly understood. The link with breast cancer is rare, though sporadically reported. Vasculitis in this context may occur before, during, or after cancer diagnosis or treatment. Notably, only two cases of breast cancer-associated vasculitis have been reported in patients aged 80 or older. Paraneoplastic vasculitis typically resolves with treatment of the underlying malignancy. However, given the presence of metastatic disease in this patient, immunosuppressive therapy with azathioprine was needed, resulting in complete resolution of lesions.

Computed coronary tomography angiography (CCTA) is an important diagnostic tool in patients with suspected acute coronary syndromes (ACS). We present a case of vasculitis and coronary involvement, in which CCTA provided critical insights for both diagnosis and management.