A case of cutaneous nocardiosis successfully treated with third-generation cephalosporin

Abstract

Dear Editor, Cutaneous nocardiosis is a type of skin and soft-tissue infection caused by Nocardia species, a kind of bacteria isolated from the environment. Sulfamethoxazole is the priority choice of oral medication,[1] but impaired renal function is a concern. Herein, we present a case successfully treated with oral cefixime as an alternative. An 87-year-old man with diabetes mellitus, congestive heart failure, and stage 4 chronic kidney disease (estimated glomerular filtration rate: 28.5 mL/min/1.73 m²) suffered from painful lesions on the face after falling to the ground. Abrasion wound and ecchymosis developed initially, so he was brought to local clinic for management. The patient did not receive systemic immunosuppressant or glucocorticoids, nor was he diagnosed with malignancy or an autoimmune disease. Topical antibiotic was given, and his wound gradually healed. However, pustular eruptions at the trauma site developed 1 week later. Cellulitis was impressed first, so topical fusidic acid cream and oral doxycycline were applied after obtaining the wound culture. The primary wound culture yielded coagulase-negative Staphylococcus epidermidis, which indicated colonization or contamination of the specimen. His symptoms also did not improve after 1-week oral antibiotic treatment. He then came to the dermatology clinic. Physical examination revealed erythematous firm nodules and pustules with erythematous-based patches on the left cheek [Figure 1a]. The patient was afebrile then.Figure 1: Clinical presentation: (a) before treatment: erythematous nodules and pustules on left cheek; (b) after treatment: erythema and pustules on left cheek resolved.Differential diagnoses included bacterial cellulitis, atypical infection (e.g. sporotrichosis, nocardiosis, tuberculosis, nontuberculous mycobacterium, or leishmaniasis), or Majocchi granuloma. He then received skin biopsy with tissue culture. Pathology report revealed suppurative microabscesses with aggregation of histiocytes [Figure 2a]. Immunohistochemistry stain showed negative for Gram’s stain [Figure 2b], periodic acid–Schiff stain [Figure 2c], or acid-fast stain [Figure 2d]. The tissue culture yielded Nocardiabrasiliensis, so cutaneous nocardiosis was diagnosed. The chest X-ray only showed enlarged heart size without increased infiltration or nodule at the lung field. Considering the impaired renal function of the patient, sulfamethoxazole was not given. We prescribed alternative treatment with oral cefixime 100 mg twice a day. After 4-week treatment, the skin lesion of the patient almost resolved [Figure 1b].Figure 2: Histopathological investigation: (a) Histopathology stain of the skin biopsy revealed suppurative microabscesses with aggregation of histiocytes (H and E, ×200); immunohistochemical stain of skin biopsy revealed negative for (b) Gram’s stain (×200), (c) periodic acid–Schiff stain (×200), and (d) acid-fast stain (×200).Cutaneous nocardiosis is skin and soft-tissue infection from a kind of filamentous bacteria which is aerobic Gram-positive. The portal of entry includes direct inoculation due to trauma and bloodstream in immunocompromised host. Cutaneous manifestation may present as nodular-pustular lesions with or without sporotrichoid distribution, cellulitis, or ulcerative lesions.[2] The most common extracutaneous lesion is pulmonary nocardiosis, especially in immunosuppressed patients. The first-line treatment is sulfonamides, such as sulfamethoxazole with or without trimethoprim. Other alternatives include minocycline, amikacin, imipenem, tigecycline, and third-generation cephalosporins.[3] Combination therapy is suggested in severe or complicated cases. In patients with immunosuppressive states, prolonged antibiotic use for 1–4 months is highly suggested. The prognosis of primary cutaneous nocardiosis is good when appropriate antibiotic therapy is given. Back to our patient, the treatment options of sulfamethoxazole and amikacin were excluded due to impaired renal function. Minocycline was not feasible because of a previous lack of response to doxycycline. The patient refused in-hospital treatment, so imipenem and tigecycline could not be given. Therefore, oral form third-generation cephalosporin may be an appropriate option based on previous article reviews and the response of the patient’s clinical presentation. In conclusion, cutaneous nocardiosis may be derived from local trauma related to plants and soil, resulting in abscess, cellulitis, or lymphocutaneous nodules in a sporotrichoid pattern. Sulfamethoxazole is the first-line therapy, but third-generation cephalosporin may be an effective alternative for patients who cannot tolerate sulfa drugs. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that his name and initials will not be published and due efforts will be made to conceal his identity, but anonymity cannot be guaranteed. Data availability statement Data sharing not applicable to this article as no datasets were generated or analyzed during the current study. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.