What is the recommended treatment for a patient with anorexia (loss of appetite) and parotid swelling?

Anorexia and Parotid Swelling: Diagnostic and Treatment Approach

Primary Diagnosis: Eating Disorder-Related Sialadenosis

The combination of anorexia and parotid swelling is pathognomonic for eating disorder-related sialadenosis, a non-inflammatory condition affecting salivary glands secondary to malnutrition and purging behaviors. 1, 2

This presentation represents a distinct clinical syndrome combining dysorexia (loss of appetite), sialomegaly (salivary gland enlargement), and often amenorrhea in women, where both the parotid swelling and hormonal disturbances are secondary to poor nutritional status. 1

Diagnostic Confirmation

Clinical Features to Assess

• Bilateral parotid enlargement is the hallmark finding, occurring in approximately 66% (27 of 41) of bulimic patients, with possible involvement of submandibular glands and even palatal minor salivary glands 3, 4, 5
• Dental erosions are present in the majority of patients with eating disorders and correlate significantly with parotid enlargement, especially in bulimic patients with an anorectic prephase 4
• Hyperamylasemia occurs commonly and helps confirm the diagnosis, with serum amylase levels significantly elevated compared to healthy controls 3, 4
• Menstrual irregularities (hypomenorrhea or amenorrhea) in women, representing hypothalamic dysfunction secondary to malnutrition 1

Diagnostic Workup

• B-scan ultrasonography is the most important non-invasive diagnostic tool to assess the nature of parotid enlargement and differentiate sialadenosis from other causes 3
• Serum amylase measurement to document hyperamylasemia 3, 4
• Fine-needle aspiration cytology or biopsy is rarely needed but shows characteristic sialadenosis features (acinar cell hypertrophy without inflammation); consider intra-oral biopsy of palatal minor salivary glands if accessible to avoid invasive extra-oral procedures 5

Treatment Strategy

Step 1: Address the Underlying Eating Disorder

The parotid enlargement is transient and resolves with nutritional rehabilitation—surgical intervention is only rarely required. 3

• Psychiatric consultation is mandatory, as patients often deny their eating disorder and the parotomegaly may serve as a diagnostic primer 3
• Nutritional rehabilitation is the definitive treatment, as the sialadenosis results directly from malnutrition and will not resolve without addressing the root cause 1, 2

Step 2: Pharmacological Management of Anorexia

For patients with months-to-weeks life expectancy where increased appetite is important for quality of life, initiate mirtazapine 7.5-15 mg at bedtime as first-line therapy. 6, 7

Mirtazapine (First-Line)

• Dosing: Start 7.5 mg at bedtime, titrate to maximum 30 mg at bedtime; requires 4-8 weeks for full therapeutic trial 6
• Dual benefit: Addresses both depression (common in eating disorders) and appetite simultaneously 6, 7
• Expected outcomes: Mean weight gain of 1.9 kg at 3 months and 2.1 kg at 6 months, with approximately 80% experiencing some weight gain 6
• Side effects are therapeutic: Sedation, increased appetite, and weight gain are beneficial in this population 7

Alternative Options if Mirtazapine Fails

• Megestrol acetate 400-800 mg daily: Efficacy of 1 in 4 patients experiencing increased appetite and 1 in 12 achieving measurable weight gain 8, 9, 7
  • Critical warning: Risk of thromboembolic events, edema, vaginal spotting, and higher mortality rates compared to placebo 6
  • Contraindication: May attenuate benefits of resistance training and cause muscle strength deterioration 6
• Dexamethasone 2-8 mg daily: Reserve for very short-term use (1-3 weeks maximum) due to rapidly diminishing benefits and muscle wasting effects 8, 7

Step 3: Nutritional Interventions

• Nutritional counseling with oral supplements for patients undergoing treatment that affects nutritional intake 9
• Fortified foods and oral nutritional supplements when dietary intake falls to 50-75% of usual intake 6
• Calorie-dense, high-protein supplementation to complement pharmacologic intervention 7

Step 4: Address Reversible Contributors

• Pain management: Uncontrolled pain suppresses appetite 9
• Constipation relief: Causes early satiety and discomfort 9
• Nausea/vomiting control: Use appropriate antiemetics 9
• Oropharyngeal candidiasis treatment: Common in malnourished patients 7

Monitoring Requirements

• Regular weight monitoring to assess response to interventions 9
• Serum amylase levels to track improvement in salivary gland dysfunction 3, 4
• Thromboembolic surveillance if using megestrol acetate 9
• Reassessment at 9 months: Consider dosage reduction of mirtazapine to reassess need for continued medication 6
• Discontinuation protocol: Taper mirtazapine over 10-14 days to limit withdrawal symptoms 6

Critical Pitfalls to Avoid

• Do not perform unnecessary surgery: The parotid enlargement is transient and resolves with nutritional rehabilitation 3
• Do not use appetite stimulants in dementia patients without depression: Evidence shows no consistent benefit and potentially harmful side effects 6
• Do not use corticosteroids long-term: Dexamethasone causes muscle wasting (myopathy), directly worsening cachexia 7
• Do not overlook the psychiatric component: Patients often deny their eating disorder, and failure to address the underlying behavioral pathology will result in treatment failure 3