Ecthyma gangrenosum (EG) is a necrotizing skin lesion that typically begins as an erythematous or hemorrhagic area and progresses to a necrotic ulcer with a black eschar. EG is most commonly associated with Pseudomonas aeruginosa infections in immunocompromised individuals, though other pathogens have been implicated in rare cases. We present an unusual case of EG originating in the oral cavity of an immunosuppressed patient, accompanied by extensive ecchymoses and polymicrobial infection, notably without P. aeruginosa involvement. This report highlights the atypical clinical and pathologic features of the case and reviews the broader spectrum of microorganisms associated with EG.

Ecthyma gangrenosum (EG) is a relatively rare cutaneous infection that is most commonly caused by Pseudomonas aeruginosa (P. aeruginosa). EG predominantly affects immunocompromised individuals and can be categorized into bacteremic and non-bacteremic types. Despite this distinction and clinical evidence supporting the existence of the non-bacteremic type of EG, the long-held belief that bacteremia must be present for the diagnosis of EG persists. This report describes a case of a 78-year-old Caucasian male with Waldenström macroglobulinemia (WM) undergoing chemotherapy, who presented with a non-tender, necrotic, gangrenous ulcer on the left side of his groin. Physical examination revealed a sharply demarcated black eschar measuring 3 cm in diameter with an erythematous border. Laboratory results showed a white blood cell count of 1.34 K/mcL, red blood cell count of 4.07 million/µL, and platelet count of 126 K/mcL, indicating marked pancytopenia. Blood cultures obtained on the day of admission were negative. Tissue cultures from a punch biopsy were positive for P. aeruginosa and Enterococcus faecalis (E. faecalis). Initial empiric treatment consisted of intravenous cefepime and vancomycin. Full surgical debridement was performed on day four. Following the procedure, the patient was discharged the same day on amoxicillin-clavulanate and ciprofloxacin to be taken for 10 days and was instructed to follow up with wound care. The lesion site showed improvement with the antibiotic regimen, both before and after debridement. EG can manifest without bacteremia, especially in immunosuppressed individuals with environmental risk factors. In this case, the patient's history of WM, use of the chemotherapeutic agent zanubrutinib, and neutropenia compromised innate host defenses. These factors, combined with a recent hospitalization that included the administration of broad-spectrum antibiotics, created a favorable environment for bacterial growth. This report serves as a reminder that prompt initiation of empiric antibiotics, timely biopsy of the lesion, and subsequent tissue cultures to determine bacterial susceptibility are essential for a favorable outcome when non-bacteremic EG is suspected.

Calciphylaxis is a rare condition that is not well understood but is known to carry significant morbidity and mortality. We present a 44-year-old male with a history of end-stage renal disease on dialysis complaining of increasingly painful chronic wounds. The patient's physical exam was remarkable for ulcerated, bilateral anterior leg wounds with large areas of eschar along with purulent drainage. He was admitted to the hospital for intravenous antibiotics, wound care, and specialist consultation for treatment of calciphylaxis. This case report provides an overview of the key clinical features of calciphylaxis and reviews potential treatment strategies for this life-threatening condition.

Anthrax is a spore-forming rod that is readily found in soil in tropical environments. Anthrax has many desired features that make it an optimal biologic weapon because it has the following features including high morbidity and mortality rates, low infective dose, lack of rapid available diagnostic tests, lack of universally available effective vaccine, potential to cause anxiety and fear, wide availability of pathogen, feasibility of production, environmental stability, and potential to be weaponized. In recent history, anthrax has been used as an agent of biologic warfare in both the United States and abroad. In 1979, an accidental release of anthrax spores from a Soviet Union bioweapons facility in Sverdlovsk, Russia infected 77 people with diagnostic certainty. Of those infected 66 died within 1 to 4 days following the onset of symptoms. In September 2001, a government employee of the US Army Research Institute for Infectious Disease intentionally distributed anthrax spores through the US Postal Service. Eleven people who came in contact with the infected mail were later diagnosed with inhalational anthrax, and 5 died from their illnesses. Eleven additional patients were diagnosed with cutaneous anthrax, all of whom survived.

Degos disease, or malignant atrophic papulosis (MAP), is a rare vasculopathic disorder that commonly involves the skin, gastrointestinal tract, and central nervous system. Diagnosis is made through recognition of characteristic histopathologic features of cutaneous lesions. Here, we report a 58-year-old male who initially presented with a penile eschar exhibiting vascular dilation, hyalinization of superficial dermal vessels, and hemosiderin deposition. Later, he developed scattered erythematous papules with central porcelain-white scarring; biopsies of these lesions exhibited features histopathologically consistent with MAP, including wedge-shaped necrosis extending from the epidermis into the deep dermis, dermal mucinosis, and vascular occlusion. Our patient subsequently developed multiple bowel perforations and ultimately succumbed to the disease. Recognition of various distinctive histopathologic features, including the diverse findings associated with penile ulceration, is important for prompt diagnosis and early initiation of treatment. As such, we review the clinicopathologic features reported in penile ulcerations among patients with MAP.

We present the case of a 60-year-old immunocompromised man who presented with two pruritic pink-red indurated nodules with overlying scale and focal areas of ulceration on his left dorsal and left medial forearm, which evolved over a 2-month period. The pathology showed numerous fungal hyphae present that were pauci-septate with various branched angles and variable hyphal thickness. Fungal cultures grew Rhizopus species and a universal fungal PCR detected the Rhizopus oryzae complex. Based on the clinicopathologic correlation, the diagnosis of cutaneous mucormycosis was made. Cutaneous mucormycosis is an aggressive fungal infection of the Mucorales family occurring after the inoculation of fungal spores in disrupted skin. It usually presents as a necrotic eschar but can also present as cellulitis that evolves into a necrotic ulcer. A prompt diagnosis is critical for the effective management of cutaneous mucormycosis. The treatment includes an immediate systemic treatment with amphotericin B and a surgical debridement of the necrotic regions. Given the wide range of presenting symptoms, clinical suspicion for this emergent condition must remain high in immunocompromised and diabetic patients.