A 13-month-old female with no pertinent medical history was admitted with a one-week history of left temporal swelling. The patient's mother reported no previous trauma to the area and a lack of apparent tenderness on palpation. The mother also stated that the patient experienced a short viral illness approximately one to two months previous to presentation with apparent trismus. The patient had no residual symptoms of the viral illness and no longer appeared to demonstrate decreased range of motion of the jaw or decreased oral intake. The patient was up to date on all immunizations and had a normal birth and developmental history. All questions on review of systems were negative except for a temperature of 37.7 C. On examination there was boggy, non-tender, non-erythematous swelling of the left temporal region. The patient was otherwise normocephalic with no other positive findings. Investigations revealed a white blood cell count of 17.6 K/uL (normal range 6-17.5 K/uL) with neutrophilia and C-reactive protein of 17.0 mg/dL (normal range 0.0-0.5 mg/dL).
CT of the maxillofacial region and sinuses with contrast showed an indeterminate process centered over the left temporalis muscle with considerations including vascular or lymphatic malformation, myositis, or injury (Fig. 1). Magnetic resonance angiography and venography of the brain without contrast showed normal venous and arterial anatomy. MRI of the brain with and without contrast showed the enhancing mass overlying the left temporalis muscle with no cranial involvement and was otherwise normal. Infection was suspected from the clinical picture and the patient was discharged with a one-week course of amoxicillin-clavulanic acid and scheduled for follow-up with otolaryngology.
On follow-up one week later, the patient had finished the antimicrobial with no reduction in temporal swelling. The mother reported no further complications or developments with the exception of a mild cough and rhinorrhea. The patient was scheduled for ultrasound-guided fine needle aspiration of the mass in order to further evaluate.
However, the patient was readmitted six days after being seen in the clinic due to further enlargement of the mass. The mother stated that the swelling had nearly tripled in size, had become tender to touch, and the patient had decreased jaw opening. Repeat laboratory investigation showed a normal white count, but elevated erythrocyte sedimentation rate of 84 mm/hr (normal range 0-20 mm/hr) and C-reactive protein of 2.2 mg/dL (normal range 0.0-0.5 mg/dL). Repeat imaging with CT of the head with contrast showed enhancing soft tissue masses in the left frontal scalp, left masticator space, and left parotid space. MRI of the face and sinuses with and without contrast showed an infiltrative lesion in the left temporalis region with extension along the lateral aspect of left orbit and inferiorly into the infratemporal fossa. Differential considerations included cranial fasciitis or neoplastic processes such as rhabdomyosarcoma or fibrosarcoma. Infection was considered unlikely due to the stability in size compared to the previous admission's imaging (Fig. 2).
On day 2 of admission, excisional biopsy with incision and drainage of the left temporal region was performed. A 1 cm incision was marked over the most edematous region hidden in the hairline. Sharp incision was created through the skin down to temporal muscle. A wedge of temporalis muscle was removed and sent for histopathological evaluation. Blunt dissection was then taken down to the calvarium and down to the lateral orbital rim. Keratin debris with hair follicles were encountered and sent for histopathological evaluation. Cavity walls were also biopsied and sent for histopathological evaluation. The wound cavity was then copiously irrigated and suctioned and closed in layers.
All aerobic, anaerobic, and fungal cultures showed no growth. Histopathologic examination of the temporalis muscle and debris showed granulation tissue with nonspecific acute inflammation, lymphocytes, and macrophages. The patient was discharged with clindamycin 30 mg PO three times daily for seven days and scheduled for follow-up in otolaryngology clinic again.
During the next two clinic visits for follow-up, the course of antimicrobials were completed and the mother reported reduction in swelling and improvement in jaw opening. However, approximately one month later the patient presented to a follow-up visit with recurrence of left temporal swelling, this time with erythema and edema of the area. A seven-day course of amoxicillin-clavulanic acid was started and CT of the maxillofacial region with contrast and 3D reconstruction was performed in preparation for surgical removal. The imaging showed a stable size of the infiltrative lesion in the left temporalis muscle extending into the infratemporal fossa with underlying bony hyperostosis. There were enlarged lymph nodes in the left anterior parotid region. Differential considerations again included cranial fasciitis versus a neoplastic process (Fig. 3).
The patient was admitted one month later for excision of the left temporoparietal lesion. A 4 cm extended incision was performed at the site of the previous incision. At this point, sharp dissection was carried through the skin, subcutaneous tissue, and loose connective tissue until encountering the temporalis muscle. The muscle was noted to be very inflammatory with exudative material and some purulence. Samples of the exudate were sent for culture. Exudative tissue overlying the temporalis muscle was curetted off of the muscle and skin. This dissection was carried medially to the point of the epicenter of the lesion. There was noted to be a tract extending from the deeper tissue to the overlying skin. The tract was followed and removed. All tissue was sent for permanent pathology. Due to a small amount of bleeding, a TLS drain was placed during the postoperative period.
Pathology of the left temporal lesion showed granulation tissue with nonspecific acute and chronic inflammation. Cultures of the region returned showing 3+ beta lactamase negative Aggregatibacter aphrophilus colonies. Sensitivities of the organism were not available, so empiric intravenous azithromycin 94 mg once daily was begun. Bartonellosis and coccidioidomycosis serologies as well as a tuberculosis interferon-   release assay were done at this time. The patient was discharged on day three of admission after removal of the TLS drain and transitioned to oral azithromycin 100 mg daily for seven days and cefixime 100 mg daily for ten days.
Upon follow-up with both pediatric infectious disease and otolaryngology, the patient had improved with no complications. The incision healed appropriately, antimicrobials were finished and discontinued, and bartonella, coccidioidomycosis, and tuberculosis testing was negative. The most recent laboratory investigations approximately one month after the final hospital admission showed a white count of 7.3 K/uL (normal range 6-17.5 K/uL), erythrocyte sedimentation rate of 13 mm/hr (normal range 0-20 mm/hr), and C-reactive protein of 0.1 mg/dL (normal range 0.0-0.5 mg/dL). The mother stated that swelling, trismus, fevers, and other symptoms have not recurred.