Title: Streptococcus pneumoniae Parotitis in a Patient with Poor Oral HygieneAuthor/corresponding author and Affiliation: Dr Mohammad Salhab, Centre for Bone Disease and Surgery (CBDS), Beirut, Lebanon. Email: [email protected]: We report a case of a 23-year-old female university student with poor oral hygiene who presented with recurrent right parotid gland swelling and pain. Despite multiple courses of antibiotics, the patient experienced persistent symptoms. Methodology: Magnetic resonance sialography revealed two intraductal stones in the right parotid gland. Purulent discharge from the parotid duct grew Streptococcus pneumoniae . Results: The patient was successfully treated with levofloxacin, parotid massage, and hydration. She was also advised to receive pneumococcal vaccination and reported no side effects after the first dose. Conclusion: This case highlights the importance of considering S. pneumoniae as a potential cause of parotitis in patients with poor oral hygiene, the role of imaging, microbiology, and targeted therapy in managing recurrent parotitis, and the potential benefits of pneumococcal vaccination in preventing future infections.KeywordsStreptococcus pneumoniae; parotitis; pain; vaccination; magnatic saliogram.Key Clinical Message: Streptococcus pneumoniae should be considered as a potential cause of recurrent parotitis, especially in patients with poor oral hygiene. Comprehensive management includes targeted antibiotic therapy based on culture results, addressing underlying factors like sialolithiasis, and considering pneumococcal vaccination to prevent future infections. This case highlights the importance of thorough diagnostic workup and multidisciplinary approach in managing challenging parotitis cases.Introduction: Acute bacterial parotitis is an uncommon condition, usually caused by Staphylococcus aureus or oral anaerobes (McQuone 1999). Streptococcus pneumoniae is a rare cause of parotitis, primarily seen in immunocompromised individuals (Yii, Tan, and Fong 2016). Risk factors for parotitis include poor oral hygiene, dehydration, and ductal obstruction (Brook 1992). The management of acute parotitis that can develop to acute on chronic suppurative condition can be challenging and also impactful on patient’s quality of life (Patel, Scott, and Cunningham 2017). We present a case of recurrent S. pneumoniae parotitis in a young female with poor oral hygiene and subacute sialolithiasis and discuss the role of pneumococcal vaccination in preventing future infections.Case History and Examination: A 23-year-old female university student presented to the ENT clinic with a 10-day history of right parotid gland swelling that became painful over the last 48 hours. She had no previous episodes but reported a few episodes of colds and sore throat during the past year. The patient was a smoker with poor oral hygiene, including several dental caries, and did not regularly brush her teeth. She was also anaemic and vitamin D insufficient. She had no significant medical or surgical history and no family history of parotitis or cancer. She had a compete up to date record of vaccinations including mumps, measles, and rubella.Method: On examination, she had right parotid gland swelling and enlargement of submental, submandibular, and neck lymph nodes. Oral examination revealed poor oral hygiene and dry mucosa without halitosis. Bimanual palpation of the parotid gland showed a mobile soft, painful swelling.Results: Investigations including FBC, CRP, ESR, electrolytes, vitamin D, LFTs, TFTs, calcium, lipid profile, and urinalysis were unremarkable except for vitamin D insufficiency. The patient was treated with amoxicillin for one week and vitamin D3 supplementation and discharged.Two weeks later, the patient returned with recurrent right parotid swelling. Symptoms had initially improved with antibiotics but recurred two days after completing the course. A ”wait and watch” approach was adopted, but the patient reported fluctuating swelling and pain. She was given another course of amoxicillin-clavulanate and discharged.One month later, the patient presented again with painful parotid swelling. An MRI sialogram demonstrated a relatively enlarged and hyperintense right parotid gland measuring 59x42x29mm, without nodules or ductal dilation-see fig 1a. Contrast injection revealed two intraductal stones- see fig 1b. Interestingly, blood works, inflammatory markers and cultures were negative. The patient was advised to maintain hydration and discharged.