Subgaleal abscess
Subgaleal abscesses and skull osteomyelitis are rarely encountered today.
The subgaleal space is the between the galea aponeurotica and periosteum of the cranial bones, subgaleal abscess may result from hematogenous infection or contiguous spread, and the diagnosis may not be initially obvious. The predominant organism isolated from post-traumatic and post-surgical scalp infections is Staphylococcus aureus.
Diagnosis and management will be guided by head CT scan, management of subgaleal abscess should focus on effective intravenous antibiotic therapy, immediate surgical drainage of abscess and debridement of necrotic tissue.
Subgaleal abscess is a rare complication, imaging can prevent serious complications. Negative pressure wound therapy is an invaluable tool for closure of the wounds 1).
Etiology
Reports of these entities usually describe an underlying pathology such as trauma or puncture wounds which account for direct inoculation or contiguous spread of microorganisms.
Acute bacterial sinusitis 2) Surgical correction of craniosynostosis 3)…
Treatment
Although the diagnosis and management of a secondary subgaleal abscess may be straightforward, the same cannot be said for a primary or de novo subgaleal abscess 4).
Case series
Goodman SJ, Cahan L, Chow AW. Subgaleal abscess: a preventable complication of scalp trauma. West J Med. 1977 Aug;127(2):169-72. PubMed PMID: 898950; PubMed Central PMCID: PMC1237748.
Case reports
A case of extensive subgaleal abscess that presented as an infected scalp sebaceous cyst, in male diabetic patient, its management and the role of vaccum assisted closure (V.A.C.) dressing which was never described in such atypical presentation 5)
Spontaneous subgaleal abscess associated with lung adenocarcinoma: first description of this unusual association 6).
Spontaneous skull osteomyelitis with subgaleal abscess due to Kocuria rosea 7).
A 47-year-old immunosuppressed woman presented with fever, altered level of consciousness, dysphasia, and a left occipital subgaleal fluctuant mass after acupuncture for headaches in the same area. Imaging demonstrated subgaleal and epidural collection localized in the left occipital region. She underwent urgent surgical evacuation of both collections. Cultures from intraoperative specimens grew Streptococcus anginosus. The patient started targeted antibiotic treatment leading to complete recovery.
This is the first report of intracranial abscess after acupuncture. Given the worldwide application of this alternative treatment, physicians, acupuncturists, and the general public should be aware of the possibility of this rare but serious complication 8).
A case of a 64-year-old Sri Lankan Sinhalese man with prolonged fever and constitutional symptoms with a neglected swelling over the back of the scalp who was found to have an abscess in the subgaleal space of the scalp during surgical drainage. Burkholderia pseudomallei was isolated in pus culture, and melioidosis serology was highly positive. The patient was treated with ceftazidime for 2 weeks, followed by co-trimoxazole for another 3 months. He made a complete clinical recovery with normalization of inflammatory markers. This is the first case of subgaleal abscess following melioidosis infection reported in the literature.
Abscesses in anatomically unusual locations should raise suspicion for melioidosis infection, particularly among patients with risk factors such as diabetes mellitus 9).
A case of an infected SGH in an 8-month-old following closed skull fracture. The patient presented with scalp swelling 1 day after falling 3 feet. Initial evaluation found a nondisplaced skull fracture on computed tomography. She was discharged following an uneventful 23-hour observation. Three days later, she developed symptoms concerning for a viral upper respiratory tract infection and received symptomatic treatment. Nine days after injury, she returned with continued fevers, irritability, and significant increase in scalp swelling. Magnetic resonance imaging showed a subgaleal abscess with osteomyelitis. Needle aspiration revealed an infected hematoma with cultures positive for Streptococcus pneumoniae, treated with intravenous ampicillin. Purulent drainage from an enlarging necrotic needle aspiration site required subsequent surgical debridement of the subgaleal abscess with drain placement. She recovered well following surgery and intravenous antibiotics. Physicians should be aware that SGH carries a risk of serious morbidity and mortality. SGH can serve as a nidus for infection, typically from skin barrier breakdown or, as in this case, hematogenous spread. Early recognition, appropriate antibiotic therapy, and surgical debridement are critical in treating infected SGH 10).
Chang et al. reported an infected SGH with abscess formation as a complication of early-onset Escherichia coli sepsis in a term neonate. The patient was discovered to have SGH soon after birth. Early-onset E. coli sepsis developed on Day 3 of life. The SGH became infected, with abscess formation 1 week later. The infected SGH was probably due to direct hematogenous spreading of sepsis. The patient was successfully treated without complications. Clinicians should be aware that SGH is a potential site of infection and infection may be caused either by direct hematogenous extension or from traumatic scalp lesions. Appropriate antibiotic treatment and surgical debridement are necessary when an infected SGH occurs 11).
Chou et al. reported on an elderly female who suffered from forehead carbuncle with intractable headache, later confirmed as having subgaleal abscess. Physicians should pay special attention to elderly and immune-compromised patients with carbuncles located in the middle of the face, especially when accompanied by intractable headache, to avoid poor outcome 12).
A 14-year-old boy with a rare combination of periorbital cellulitis, subgaleal abscess and superior sagittal sinus thrombosis following a late presentation of unilateral frontal sinusitis.
Following multiple surgical procedures, and antimicrobial and anticoagulation therapy, the patient made a full recovery.
Serious sinusitis complications still occur and can do so in unusual combinations with minimal clinical signs. Systemic anticoagulation therapy is considered safe practice in the management of cerebral venous sinus thrombosis and may reduce morbidity and mortality 13).
A 5-year-old child presented to the emergency department with a three-week history of fever associated with drowsiness and left parietal headache, and a week’s history of swelling on the left frontoparietal soft tissue. He had suffered a penetrating scalp injury four month ago. On physical examination, there was a tender swelling with purulent stream on the lateral half of his scalp. His vital signs are within normal limits. Plain X-ray of the skull showed a lytic lesion on the left frontoparietal bone. A cranial computed tomography (CT) scan demonstrated a large subgaleal abscess at the left frontoparietal region. SBO possesses a high morbidity and mortality; therefore, prompt diagnosis and appropriate treatment are mandatory to prevent further complications and to reduce morbidity and mortality significantly 14).
A case of bacterial meningitis, subgaleal, subdural, and epidural empyema due to Pasteurella multocida by a rabbit licking that resulted in neurological complications and a prolonged recovery period 15).
A preterm infant who developed scalp abscess and E. coli sepsis following a scalp electrode. Onyeama et al. recommend a careful examination of babies with a history of fetal electrode monitoring as this could be a nidus for local and generalised infection 16).
A 12-year-old girl presented with a swollen right eye with three days of pain and a diffused swollen frontal region and head lasting for one day. On the computed tomography with contrast, diffused collection was detected in the subgaleal regions and subperiosteal of the right orbita. It was observed that she had bilateral maxillary, ethmoidal, and frontal sinusitis and an infected bilateral middle concha bullosa in the right side. No symptoms of intracranial complication and osteomyelitis in the frontal or other calvarial bones were determined. This case presentation is thought to be the first one in literature that is an acute sinusitis without an intracranial complication and osteomyelitis, but with a diffused subgaleal abscess resulting from a subperiosteal abscess 17).