What is the treatment for sialoadenitis and myositis?

Treatment of Sialoadenitis and Myositis

Sialoadenitis Treatment

For bacterial sialoadenitis, cephalosporins and fluoroquinolones are the recommended first-line antibiotics due to their superior pharmacokinetics in saliva and coverage of the bacterial spectrum implicated in salivary gland infections. 1

Acute Bacterial Sialoadenitis

• Intravenously administered cephalosporins achieve the highest concentrations in saliva, followed by orally administered cephalosporins and fluoroquinolones 1
• These antibiotics exceed the minimal inhibitory concentrations of bacteria commonly causing sialoadenitis (Staphylococcus aureus, Viridans streptococci, gram-negative strains, and anaerobes) 1
• Phenoxymethylpenicillin and tetracyclines should be avoided as they do not reach bactericidal levels in saliva 1
• Surgical drainage may be necessary if abscess formation occurs 2

Obstructive Sialoadenitis

• Treatment focuses on removing the obstruction (stones, strictures) 2
• Sialendoscopy has emerged as the leading diagnostic technique and therapeutic intervention, especially in pediatric cases 3
• Sialendoscopy is both safe and effective as a gland-preserving treatment 3

Radiation-Induced Sialoadenitis

• Preventive measures include sialogogues (medications that stimulate saliva production) 4
• Local massage of the affected gland 4
• Conservative drug therapy for symptom management 4
• Consider vitamin E supplementation 4

Myositis Treatment

High-dose corticosteroids (prednisone 1 mg/kg/day orally or methylprednisolone IV for severe cases) should be started immediately upon diagnosis of myositis, with concurrent initiation of a steroid-sparing agent to allow for eventual steroid tapering. 5

Initial Management

• For mild myositis (Grade 1): Start prednisone at 0.5 mg/kg/day if creatine kinase (CK) and/or aldolase are elevated and muscle weakness is present 6
• For moderate myositis (Grade 2): Prednisone or equivalent at 0.5-1 mg/kg/day 6
• For severe myositis (Grade 3-4): Prednisone 1 mg/kg/day or methylprednisolone 1-2 mg/kg IV or higher dose bolus 6
• Steroid-sparing agents should be initiated concurrently and include methotrexate (15-25 mg weekly), azathioprine (2-3 mg/kg/day), or mycophenolate mofetil (2-3 g/day) 6, 5

Severe or Refractory Disease Management

• Consider intravenous immunoglobulin (IVIG) at 2 g/kg divided over 2-5 days for patients with severe disease or inadequate response to initial therapy 6, 5
• Plasmapheresis should be considered in cases with poor response to corticosteroids or in life-threatening situations 6, 5
• Other immunosuppressant therapies including biologics (e.g., rituximab), TNFα or IL-6 antagonists if symptoms worsen or no improvement after 2 weeks 6
• Cyclophosphamide or cyclosporine may be considered for severe or refractory cases 6, 5

Monitoring and Follow-up

• Serial measurements of muscle enzymes (especially CK) and inflammatory markers should be performed regularly 6, 5
• Regular assessment of muscle strength and function is necessary 5
• MRI can be useful to monitor treatment response 6, 5
• Patients with concomitant myocarditis and/or myasthenia gravis have a particularly poor prognosis with high mortality rates 6, 5

Prevention of Corticosteroid Adverse Effects

• Monitor bone health with routine dual-energy x-ray absorptiometry 6
• Prescribe calcium and vitamin D supplements; if osteoporosis is evident, add a bisphosphonate 6
• Consider Pneumocystis prophylaxis with trimethoprim-sulfamethoxazole if the patient is taking ≥20 mg of corticosteroids for 4 weeks or longer 6
• Be vigilant for other complications of long-term corticosteroid use: weight gain, hypertension, stretch marks, cataracts, diabetes, dyslipidemia, and corticosteroid-induced myopathy 6

Special Considerations

• If myositis is immune checkpoint inhibitor (ICPi)-induced, discontinuation of the offending agent is essential 6, 5
• For necrotizing myositis with infectious etiology, appropriate broad-spectrum antibiotics covering both aerobic and anaerobic organisms should be administered 5
• Surgical debridement may be necessary for infectious necrotizing fasciitis 5