Parotitis in children is a complex clinical problem. It is characterized by a high number of possible ethiological factors and unpredictable clinical course (1-4). Parotitis can be divided into chronic and acute parotitis.

Acute parotitis in children is usually caused by a viral or bacterial infection. The most common viral etiological factor is mumps virus (2). Other causes include mononucleosis caused by Epstein-Barr virus (EBV), as well as adenoviruses, Coxsackie viruses, influenza virus, and HIV. Bacterial acute parotitis is primarily caused by Staphylococcus aureus and Staphylococcus viridans (2).

Chronic parotitis is less common than the acute one. Chronic parotitis can be divided into the so-called chronic recurrent parotitis, parotitis due to sialolithiasis, and parotitis related to angiomas in the gland. Even less often, parotitis is a manifestation of a systemic or autoimmune disease, such as: sarcoidosis, Sjögren syndrome, cystic fibrosis, diabetes mellitus, and thyroid disorders (1, 2). Moreover, pneumoparotitis can sometimes occur, which can be idiopathic or related to an increased pressure in the oral cavity, most often occurring during balloon blowing, gum chewing, and as a result of professional exposure, for example in trumpeters and glassworkers. In children, pneumoparotitis occurs very rarely (1, 5-7).

Chronic recurrent parotitis in children is a rare disease with a multifactorial and unclear etiology. It is believed that the causes include congenital anomalies of parotid glands and their ducts, as well as recurrent infections, allergies, immunodeficiencies, and autoimmune reactions (2, 8). The role of immunoglobulin IgA is underlined, as its deficiency may lead to chronic parotitis. IgA is an immunoglobulin produced by mucous membranes, including oral and respiratory mucosa. It is thought that chronic recurrent parotitis coexists with respiratory and gastrointestinal diseases, such as asthma and celiac disease (3, 8). Chronic recurrent parotitis is diagnosed in children aged from a few months to 15-17 years of age. The most common symptom is painful swelling of one or two parotid glands without purulent discharge from duct orifice, as well as increased body temperature. The symptoms last for a few days and they resolve spontaneously, reoccurring with various frequency, from a single recurrence to several episodes a year. The diagnosis of chronic recurrent parotitis is often delayed by several months or even years, as the first episode is usually diagnosed as acute parotitis. In parotid ultrasound, characteristic lesions in the form of small hypoechogenic foci are observed, which correspond to parotid duct dilation (3, 4, 9-12). In some cases, chronic recurrent parotitis resolves spontaneously at the onset of puberty – it is then referred to as juvenile recurrent parotitis (2). Treatment method is dependent on the number of recurrences and the severity of clinical symptoms. Between the symptomatic periods, chewing gum, lemon sucking, and other salivary stimulants are advised. It is also recommended to massage and heat the gland, which enables the saliva to liquefy (2, 12). During exacerbations with significant swelling and fever, it may be advisable to introduce antibiotic treatment to prevent adhesions (2, 9, 11-14). In case of a large number of exacerbations and severe symptoms, sialoendoscopy with corticosteroid irrigation of the gland or with sialography, which, in this case, is probably not only diagnostic, but also therapeutic, may be recommended (2, 9, 11-14). The aim of the procedure is to widen parotid ducts or to induce the inflammation of the gland, which result in the exclusion of a part of the gland from saliva production (2, 9, 11-14). Treatment methods also include ligation of the parotid duct and partial superficial parotidectomy. Surgical treatment methods are controversial due to the risks of general anesthesia, the risk of facial nerve paralysis, as well as uncertain clinical outcome with possible recurrence during puberty (2, 9, 12-14).

The aim of the study was to analyze the inflammatory changes in parotid salivary glands in children, with particular regard to etiology, laboratory findings, and clinical outcome of chronic recurrent parotitis.

Between 2010 and 2017, 30 children were hospitalized in the Department of Pediatric Otolaryngology of the Medical University of Warsaw due to parotitis. For 12 children, the Department of Pediatric Otolaryngology was the first place where they reported to with salivary gland problems. Another 18 children had previously been treated and diagnosed by other departments or their pediatricians. In all the children, sialadenitis was localized in parotid glands. Age, gender, etiology of the disease, location, laboratory findings, and comorbidities were assessed. Laboratory studies included blood count, inflammatory markers (ESR and CRP), serum amylase. Ultrasound examination of the parotid glands was performed. Children with recurrent parotitis had additional tests performed, depending on the number of episodes. The tests included: rheumatoid factor in serum, serum IgA immunoglobulin, and antinuclear antibodies (ANA). In these children, additional endocrine, gastroenterological and rheumatology consultations were planned.

The cause of hospitalization for all 30 children (17 boys and 13 girls) was swelling and pain of a parotid salivary gland. In 12 children (40%), the symptoms were accompanied by elevated body temperature. In 3 children (10%), purulent discharge from duct orifice was observed. Eleven children (36%) were diagnosed with bilateral parotitis, and another 19 (64%) – unilateral parotitis.