Etiology and Routes of Infection
Osteomyelitis of the superior maxilla in infants typically occurs in those under three months of age, with a higher prevalence in newborns. The onset is acute, the condition progresses rapidly, and complications are common. Prompt diagnosis and treatment are crucial.
The main pathogen is Staphylococcus aureus, with a minority of cases caused by Streptococcus. The underlying causes are not fully understood.
Hematogenous Infection
The cortical bone of the neonatal maxilla is thin, the medullary bone is abundant and porous, and the vasculature is rich. Once an infection occurs in another part of the body (such as umbilical cord or skin infection), pathogens can localize to the maxilla through hematogenous spread, leading to infection.
Maternal Source of Infection
The neonatal maxilla is flat and wide, containing two rows of dental germs. Its gingival mucosa is thin and offers little protection. Trauma during delivery (particularly during abnormal presentations) may allow pathogens from the birth canal to invade the maxilla and cause infection.
Direct Spread from Local Infections
Local trauma, such as that caused by bottles or spoons injuring the infant's oral mucosa or dental germs, may result in localized infection. Infection can also spread from maternal mastitis when breastfeeding continues. These localized infections can extend directly to the maxilla.
Rhinogenic Infections
This may occur as a complication of nasal or sinus inflammation.
Pathology
In the initial stage, the condition presents as an acute inflammatory response and localized thrombotic phlebitis. It progresses to ischemia of bone tissue and bacterial emboli invading the marrow, ultimately resulting in suppuration and necrosis of bone tissue.
Clinical Manifestations
Systemic Symptoms
The onset is acute, and progression is rapid. High fever (above 40°C) with chills and irritability (persistent crying) are common. Convulsions, lethargy, or even coma, along with systemic signs of intoxication, may develop. Some infants may also experience digestive issues such as diarrhea.
Local Symptoms
Symptoms include nasal congestion, mucopurulent or purulent nasal discharge, and occasionally bloody discharge. The skin and soft tissue under the inner canthus and adjacent to the nose become red and swollen, with the condition progressively affecting the lower eyelid, cheek, and upper eyelid. Conjunctival edema and narrowing of the palpebral fissure may occur. The gingiva and hard palate on the affected side may appear red and swollen. If not addressed in time, abscesses may develop, which can rupture to form fistulas. In most cases, symptoms alleviate after drainage, and body temperature gradually normalizes. Fistulas may heal spontaneously. Necrotic bone or dental germs may occasionally be expelled through the fistula or nasal cavity. If necrotic bone is not completely discharged, fistulas may not heal and could result in chronic disease. Chronic cases may persist for months to years and are prone to recurrent acute exacerbations.
Diagnosis and Differential Diagnosis
The diagnosis is generally straightforward based on the history and clinical manifestations. Imaging studies in early stages have limited diagnostic value. X-rays are typically unhelpful for early diagnosis. CT scans may help detect abscesses at an earlier stage but may fail to show smaller abscesses. In later stages, imaging may reveal osteoporosis, destruction of bone, or formation of sequestra in the affected maxilla.
Early diagnosis requires differentiation from conditions such as acute dacryocystitis, simple facial cellulitis, erysipelas, or orbital cellulitis. These conditions generally present with more localized soft tissue swelling and are rare in infants under three months of age, especially in newborns.
Complications
The most common complication is septicemia. Other possible complications include bronchitis, orbital infections, and nasal cavity infections. The condition may also affect the normal eruption of permanent teeth. Additional complications such as meningitis, brain abscess, cavernous sinus thrombophlebitis, lung abscess, and toxic hepatitis are also possible.
Treatment
Early diagnosis and treatment are critically important.
Antibiotic Therapy
Since Staphylococcus aureus is the most common pathogen, penicillin and cephalosporin antibiotics are the first-line treatments. If abscesses form, adjustments to antibiotics should be based on the results of pus culture and drug sensitivity testing. Antibiotics should be continued for one week after all clinical symptoms have completely resolved, as premature discontinuation increases the risk of recurrence.
Local Therapy
Early-stage treatments may include warm compresses and physical therapy. Measures should be taken to maintain cleanliness of the nasal cavity and oral cavity. Nasal decongestants (for less than seven days) may be used to maintain ventilation and drainage. For abscesses in the lower eyelid or medial or lateral canthus, aspiration and drainage may be performed. Abscesses in the gingiva or hard palate should be incised and drained through the buccal gingiva or hard palate, avoiding scraping to prevent damage to dental germs and bone, which could lead to future deformities. Diluted antibiotic solutions may be used for local irrigation of the incision site one to two times daily. For cases with fistula formation, patency of the fistula should be maintained.
Supportive Therapy
Maintaining water and electrolyte balance, supplementing with vitamins, and ensuring adequate nutrition are essential. Severe systemic intoxication may require corticosteroids.
Management of Necrotic Bone and Fistulas
Persistent fistulas should raise suspicion of necrotic bone formation. Imaging studies can assist in diagnosis. Surgical removal of necrotic bone may promote healing of the fistula when necrosis is confirmed.
Other Measures
Residual dental misalignment or maxillofacial deformities may require corrective surgery at a later stage.