Infectious eccrine hidradenitis: sweat glands as the portal of entry for cellulitis

Neutrophilic eccrine hidradenitis (NEH) is a rare neutrophilic dermatosis involving the eccrine glands. It is commonly associated with haematological malignancy and administration of chemotherapy. An infective aetiology for NEH is termed infectious eccrine hidradenitis (IEH). Pathogens that have been associated with IEH include Nocardia, Serratia, Enterobacter sp., Staphylococcus aureus and Mycobacterium chelonae We describe a case of IEH in a patient with prolonged use of a compression sleeve for their upper limb lymphoedema. The histopathological findings of NEH and IEH are almost identical. Skin tissue culture and rapid clinical improvement with antibiotic therapy are keys in delineating the two subtypes.

Neutrophilic dermatoses as systemic diseases

Neutrophilic dermatoses (ND) are inflammatory skin conditions characterized by a sterile infiltrate of normal polymorphonuclear leukocytes. The main clinical forms of ND include Sweet syndrome, pyoderma gangrenosum, erythema elevatum diutinum, subcorneal pustular dermatosis, and their atypical or transitional forms. ND are often idiopathic, but they may be associated with myeloid hematologic malignancies (Sweet syndrome), inflammatory bowel disease or rheumatoid arthritis (pyoderma gangrenosum), and monoclonal gammopathies (erythema elevatum diutinum, subcorneal pustular dermatosis). The possible infiltration of internal organs with neutrophils during the setting of ND underlies the concept of a neutrophilic systemic disease. ND may be seen as a polygenic autoinflammatory syndrome due to their frequent association with other autoinflammatory disorders (monogenic or polygenic) and the recent published efficacy of interleukin-1 blocking therapies in their management.

Eccrine hidradenitis sine neutrophils: a toxic response to chemotherapy

We present a case of hidradenitis occurring in a patient after chemotherapy for acute myeloid leukemia (AML) in the setting of profound neutropenia. Neutrophilic eccrine hidradenitis (NEH) presents as tender erythematous papules and plaques and is often associated with chemotherapy for AML. NEH is postulated to be due to toxic injury to the sweat glands followed by neutrophilic inflammation. Alternatively, some hypothesize that NEH represents a primary neutrophilic process. Our patient's clinical presentation was similar to previously reported cases of NEH; however, degenerative changes of the sweat ducts were noted on microscopy without neutrophilic inflammation. She had fewer than 0.01 thousand neutrophils per microliter for 4 days preceding the biopsy. At the same time, a separate area of superficial skin infection developed because of Staphylococcus epidermidis and also lacked neutrophilic inflammation. The similar clinical course and shared histopathologic features between our case and NEH argue that neutrophils are a secondary response to a toxic effect rather than the primary effector in NEH. Neutrophil-poor variants of hidradenitis, both infectious and due to drug toxicity, should be considered diagnostically in neutropenic patients.

Urticarial lesions: if not urticaria, what else? The differential diagnosis of urticaria: part I. Cutaneous diseases

Acute urticaria is self-limiting, and a cause can be identified in many patients. Chronic urticaria is a long lasting disease, and patients are commonly examined for an autoimmune origin and for associated diseases. Although the diagnosis of urticaria is straightforward in most patients, it may pose some difficulties at times and it may require a careful differential diagnosis with a number of conditions. Urticarial syndromes comprise both cutaneous and systemic disorders. Part I of this two-part series focuses on the clinical and histologic features that characterize common urticaria and on the cutaneous diseases that may manifest with urticarial lesions and must be considered in the differential diagnosis.

LEARNING OBJECTIVES

After completing the learning activity, participants should be able to distinguish between the typical wheals of urticaria and urticarial lesions suggesting other diagnoses and to assess patients with urticarial lesions in order to exclude or confirm other cutaneous diseases.

Neutrophilic eccrine hidradenitis masquerading as facial cellulitis

Neutrophilic eccrine hidradenitis typically manifests as erythematous plaques on the face, trunk, or extremities. This eruption has been associated with numerous factors, but most commonly is seen with chemotherapy, particularly cytarabine. We report a 73-year-old woman with acute myelogenous leukemia who developed rapidly expansive neutrophilic eccrine hidradenitis mimicking facial cellulitis only after a course of cytarabine was followed by granulocyte-colony stimulating factor. Prompt diagnosis is imperative to prevent prolonged antimicrobial therapy.

Hidradénite eccrine neutrophilique idiopathique de l’adulte d’évolution prolongée traitée par colchicine

INTRODUCTION

Neutrophilic eccrine hidradenitis (NEH) is a rare disease belonging to the group of neutrophilic dermatoses. It has a characteristic histopathologic pattern, with necrosis of the eccrine glands and a local neutrophilic infiltrate. It occurs mostly in patients receiving chemotherapy for acute myeloblastic leukemia or, less frequently, another malignancy. Its occurrence in healthy patients is rare.

CASE REPORT

We report the case of a 56-year-old woman with no remarkable medical history who developed an erythematous papular facial eruption. Skin biopsy showed typical features of neutrophilic eccrine hidradenitis including neutrophilic infiltrate. No cause was found. The patient was successfully treated with colchicine.

DISCUSSION

This case is particular because NEH was not associated with malignant hematologic disease, solid cancer, chemotherapy, fever or any other disease, after a follow-up of 22 months. Such idiopathic NEH has been reported only rarely in adults. The second particularity is the length of the eruption, which required colchicine treatment. Clinical improvement occurred within 1 month. Because hematologic malignancies can in some cases be preceded by neutrophilic dermatitis, clinical follow-up is recommended in adults.

Neutrophilic eccrine hidradenitis heralding the onset of chronic myelogenous leukaemia

Neutrophilic eccrine hidradenitis was initially described in acute myelogenous leukaemic patients undergoing chemotherapy, suggesting a drug-induced mechanism. It has been reported in some with various neoplastic and non-neoplastic conditions as well as in healthy individuals. However, most the reported cases have been described in acute myelogenous leukaemic cases receiving chemotherapy. We describe a neutrophilic eccrine hidradenitis case unassociated with chemotherapy in a woman with chronic myelogenous leukaemia.

Neutrophilic eccrine hidradenitis secondary to topotecan

BACKGROUND

Neutrophilic eccrine hidradenitis (NEH) is a self-restricted inflammatory condition, usually secondary to chemotherapeutic agents and less frequently to other drugs such as zidovudine or various infections. NEH clinical features include erythematous, occasionally painful nodules and plaques. Histological examinations reveal neutrophilic infiltrates and degeneration of eccrine glands.

METHODS

A 45-year-old female was treated with topotecan and colony-stimulating factor for ovarian cancer.

RESULTS

The erythematous and slightly pruritic plaques on the upper and lower limbs and ear lobes appeared approximately 1 week after chemotherapy and spontaneously subsided in about 10 days, only to recur after the next drug dose. A skin biopsy revealed NEH; all skin cultures were negative.

CONCLUSION

It is believed that this patient developed topotecan-induced NEH; this relationship with therapy rather than the underlying disease rules out a paraneoplastic reaction, and negative cultures excluded infectious causes. In addition, since skin lesions recurred after CSF was discontinued, this agent was not involved. Studies relating NEH to topotecan, a topoisomerasa I inhibitor, have not reported such an event in the literature.