A curious case of upper limb infection

Introduction

Botryomycosis is a rare and chronic suppurative bacterial infection with the most common causative organism being Staphylococcus aureus.^1,2 Botryomycosis commonly presents as papules, nodules, fistulas, abscesses or ulcers with a seropurulent discharge. ³ Other terms used to describe botryomycosis include bacterial pseudomycosis, staphylococcal actinophytosis, granular bacteriosis, and actinobacillosis. The infection is usually chronic and indolent but can be disfiguring and potentially serious.

Case report

A 27-year-old farmer male presented with multiple discharging ulcerated nodules on his right arm. He gave a history of penetrating trauma with a wooden splinter after falling to the ground while working on a farm. A few weeks later, he noticed a slightly painful nodule on his right palm with intermittent blood-stained purulent discharge. He consulted a general physician in his village and was managed with a course of antibiotic and analgesic with partial relief. Over the next two months, he developed multiple papules and nodules on his arm which ulcerated and produced a blood-stained purulent discharge. Gradually, he developed a stiff right wrist Cutaneous examination showed multiple foul-smelling ulcerated nodules on his right hand and forearm. (Figs. 1, 2) There was indeed a fixed flexion deformity at the right wrist with no range of motion whatsoever.

OPEN IN VIEWER

Figure 1.

Multiple ulcerated nodules and plaques on right forearm, wrist and dorsa of hand.

OPEN IN VIEWER

Figure 2.

Image showing fixed flexion deformity at right wrist.

His full blood count showed an anaemia (Hb 100 g/l) and leucocytosis (12 × 10⁹ cell/L). Routine serum biochemistry was within normal reference ranges. Tests for HIV, hepatitis B virus (HBV) and hepatitis C virus (HCV) were negative. A radiograph of the affected limb revealed no bone involvement. Culture of the discharging skin showed growth of oxacillin resistant coagulase positive Staphylococcus aureus (Fig. 3) methicillin resistant staphylococcus aureus (MRSA) which was sensitive to clindamycin, linezolid and erythromycin. A potassium hydroxide mount did not show any fungal organism. Biopsy from one of the nodules showed chronic suppurative granulomatous pathology comprising of lymphocytes and neutrophils and bacterial colonies. A diagnosis of Botryomycosis was made. Our patient was managed as an in-patient on parenteral Linezolid 600 mg twice a day, and Amikacin 15 mg/kg. He declined surgical debridement owing to financial constraints. Subsequently, his affected wrist showed only a slight improvement in range of motion.

OPEN IN VIEWER

Figure 3.

Blood agar culture media showing characteristic colonies of Staphyloccus aureus.

Discussion

Botryomycosis is a chronic suppurative bacterial infection which can involve the skin and viscera. ³ Risk factors include alcoholism, diabetes mellitus, HIV infection, cystic fibrosis, chronic granulomatous disease, trauma and surgery.^4–10

Histopathology shows granules of causative bacteria with the appearance of sulphur granules. The cutaneous form typically presents as an ulcerated plaque or nodules that evolve over months to years to produce discharging sinuses. Diagnosis depends on identifying typical bacteria and grains in swabs taken of pus or in skin biopsy, with the absence of true fungi or aerobic actinomycetes, as found in mycetoma.

Botryomycosis must thus be clinically differentiated from mycetoma, actinomycosis, actinomycetoma, nocardiosis and tuberculosis all of which may present as swellings with sinus and discharge.

Botryomycosis usually needs a prolonged course of antibiotic therapy, according to the sensitivity of species isolated. Though surgical excision of infected lesions is normally recommended, in our case, extensive debridement necessary threatened further to worsen the morbidity. Unfortunately, patient did not return for follow-up. Telephonic enquiry revealed that he was facing difficulty in commuting from his home as local transport was not available because of the COVID-19 pandemic.