Figure 21-1 A, The lymphocutaneous lesion of the right wrist at presentation of illness. B, Transverse paraffin section stained with hematoxylin and eosin (H&E) demonstrating prominent granulomatous perineurial inflammation (arrow). Serial transverse paraffin sections showing perivascular granuloma stained with H&E (C, arrow to granuloma) and CD-68 (D, arrow to a multinucleated giant cell).
(Modified and reprinted with permission from Mauermann ML, Klein CJ, Orenstein R, Dyck PJB. Disseminated sporotrichosis presenting with granulomatous inflammatory multiple mononeuropathies. Muscle Nerve 2007;36:866–72.)
The patient was hospitalized and treated for disseminated sporotrichosis with intravenous amphotericin B for 2 weeks, followed by intravenous itraconazole. He underwent seven débridements primarily involving the right forearm. Skin pathology showed cigar-shaped budding yeasts consistent with sporotrichosis. Following his first surgery, he developed right footdrop, with numbness of the foot and the lateral aspect of the distal lower extremity. Two months later, he noticed numbness of the left foot to the level of the ankle and numbness and tingling of the left thumb. He was discharged on itraconazole solution (20 mL twice daily).
Left upper extremity erythematous nodularity continued, with serous drainage. He developed a new right chest nodule and right thigh thickening and nodularity prompting him to pursue further evaluation at our institution. He was seen 8 months after the onset of initial symptoms. Laboratory evaluation demonstrated a mildly elevated erythrocyte sedimentation rate of 36 mm/h. Magnetic resonance imaging demonstrated thick, rim-enhancing fluid collections involving the muscles in all four extremities with edema and bone infarcts. Intravenous liposomal amphotericin was instituted for ongoing disseminated sporotrichosis. Resection of bilateral thigh and upper extremity abscesses revealed necrotizing granulomatous inflammation, with periodic acid–Schiff (PAS) and Grocott’s methenamine silver (GMS) stains confirming fungal organisms consistent with sporothrix species. Laboratory data revealed no underlying immunodeficiency.
Neurologic examination demonstrated multiple mononeuropathies with moderate weakness of finger flexion, finger extension, and thumb abduction bilaterally, and of left ankle dorsiflexion and toe extension. There was severe weakness of ankle dorsiflexion, toe extension, and foot eversion, and moderate weakness of inversion and plantar flexion on the right. Fingers on the right hand and the left thumb were hyperesthetic. The lower extremities had an asymmetric (right greater than left), mild, length-dependent sensory loss to vibration, proprioception, touch, and pinprick in a stocking distribution with contact allodynia to the knees bilaterally. Patellar reflexes were reduced, and ankle reflexes were absent bilaterally.
Nerve conduction studies demonstrated severe reduction in motor and sensory amplitudes in the upper and lower limbs bilaterally. Inching studies of the left ulnar and left peroneal motor nerves showed focal conduction blocks of 50% just distal to the medial epicondyle and at the fibular head. Needle examination revealed active neurogenic findings in left ulnar, left median, left tibial, and bilateral peroneal innervated muscles. The electrodiagnostic features were most consistent with a multifocal neurogenic process due to either confluent multiple mononeuropathies or an asymmetric peripheral neuropathy. Magnetic resonance imaging of the ulnar and peroneal nerves demonstrated T2 hyperintensity without evidence of compression (preservation of fat surrounding the nerve and lack of enhancement), which is indicative of nonspecific inflammation (immune or infectious).
Right sural nerve biopsy revealed mild, multifocal fiber loss with an increased frequency of axonal degeneration (37%) and an increased number of empty nerve strands. Small and moderate collections of inflammatory cells were seen around epineurial vessels with individual cells around endoneurial vessels. Granulomatous invasion of the outer leaflet of epineurial microvessels and the perineurium was seen (see Fig. 21-1B and C) with reactivity for a macrophage (KP-1) preparation (see Fig. 21-1D). PAS and GMS stains were negative for fungal organisms. Fungal cultures from the sural nerve showed no growth.
There was clinical improvement following débridement of the abscesses. He was discharged home on liposomal amphotericin infusions. Seventeen months following initial evaluation at our institution, the patient reported resolution of his footdrop and ability to walk and jog. He stated most of his strength and function had returned. He continued to note persistent numbness, particularly in the lower limbs.