The nasal cavity, which constitutes the foremost part of the upper respiratory tract, is in contact with the external environment and is susceptible to nasal inflammation secondary to viral and bacterial infections. Viral upper respiratory tract infection and chronic rhinosinusitis are typically associated with nasal inflammation, which can cause olfactory dysfunction in addition to nasal obstruction and rhinorrhea. Olfactory dysfunction is classified into conductive, sensorineural, and central types. Sensorineural or central olfactory dysfunction is suspected in patients without any physical obstruction in the pathway from the anterior nostril to the olfactory epithelium. However, it is practically impossible to examine the olfactory epithelium and deeper olfactory pathways in humans, therefore, information on the pathophysiology of sensorineural and central olfactory dysfunction remains unclear. However, several recent basic animal mode studies have reported that nasal inflammation is accompanied by various immune responses in the olfactory bulb, an organ located within the skull. We review the immune responses elicited in the olfactory bulb secondary to nasal inflammation, focused on findings in a viral upper respiratory tract inflammation model, together with recent results observed in other models of nasal inflammation.

Aerosol therapy is an important procedure for otolaryngologists who specialize in upper respiratory infections. Since its inauguration in 2008, our clinic has emphasized the importance of improving the environment to facilitate aerosol therapy, and has installed personalized treatment booths for patient privacy and nosocomial infection control, and an exhaust duct system to prevent environmental pollution caused by excess aerosols. In addition, infection control measures have been implemented through the management of therapeutic equipment and drug solutions following the “Guide to Nebulizer Therapy for Acute Rhinosinusitis (2016 edition).” and appropriate spray settings have been implemented based on experiments to optimize aerosol spray volume.

However, the coronavirus disease (COVID-19) pandemic that began in 2020 forced a pause in aerosol therapy from March to July of the same year. As a countermeasure, the introduction of a backflow prevention system and the initial diagnosis of COVID-19 at the fever clinic made it possible to resume treatment while ensuring the safety of aerosol therapy in addition to conventional infection control measures.

For effective aerosol therapy, it is necessary to select indicated cases by making an appropriate diagnosis. For diagnosis, nasal endoscopy or computerized tomography (CT) scan are the preferred imaging techniques. Moreover, we have encountered many cases of long-COVID symptoms such as olfactory disturbance, headache, and difficulty in concentrating, which are caused by rhinosinusitis. By a correct diagnosis of long-COVID, we can expect high therapeutic effects from administering aerosol therapy. It is possible to practice safe and effective aerosol therapy even in the corona crisis by improving the treatment environment and enhancing diagnostic accuracy.

Eosinophilic chronic rhinosinusitis (ECRS) and eosinophilic otitis media (EOM) share many pathological features and are closely related to each other. We investigated the frequency of EOM in patients with ECRS and the characteristics of ECRS in those with and without EOM.

The study population comprised 49 patients with a confirmed diagnosis of ECRS who underwent endoscopic sinus surgery (ESS) between April 2016 and December 2020 in our hospital. We examined the number of ECRS cases with EOM and the characteristics (peripheral blood eosinophils, JESREC score, tissue eosinophil counts, and the number of cases associated with bronchial asthma) in cases with and without EOM.

EOM complications were present in 6 of 49 and suspected in 3 of 49 cases, with a total of 18.3% of ECRS cases with confirmed/suspected EOM complications. All of the patients with EOM had bronchial asthma, and peripheral blood eosinophils and JESREC scores were significantly higher in patients with EOM than in patients without EOM. Therefore, it is necessary to pay particular attention to the presence of EOM in ECRS complicated with bronchial asthma, high peripheral blood eosinophils, and JESREC scores.

In recent years, the number of bear sightings has increased nationwide: in FY2020, 20,887 bear sightings and 158 bear trauma cases occurred, the highest number of sightings and human injuries since 2009, when statistics were available. Bear trauma can occur throughout the body from bear blows, claws, and fangs, particularly in the head and neck region, and otolaryngology and head and neck surgeons are often involved. Checking for damage to the eye, nasolacrimal and parotid ducts, and facial nerves and treating them in collaboration with the respective specialties depending on the site and extent of the damage are necessary.

Animal trauma often involves contamination through bite wounds as well as by vegetation and dirt, and the wound margins are often complex and contused. Adequate wound cleansing and prevention of infection with antimicrobial agents, tetanus toxoid, and anti-tetanus human immunoglobulin are important. We experienced a case of facial trauma caused by a bear. The patient was a 69-year-old male member of a hunting club. A black bear was mistakenly captured in a boar trap, and when he attempted to release it, the bear attacked him, and he was taken by ambulance to a hospital. The patient had contusion wounds on the face and left forearm and damage to the right nasolacrimal duct. Preoperative tetanus toxoid and anti-tetanus human immunoglobulin were administered, and postoperative clavulanic acid/amoxicillin + amoxicillin were administered orally, and the wound was washed daily. The wound was healing well, and the patient was discharged on the 10th postoperative day. We report our case with some literature review regarding the characteristics of bear trauma and treatment considerations.

Most cases of lymphadenitis caused by nontuberculous mycobacteria (NTM) are noted in pediatric patients, with few reports in adults, except in immunocompromised patients. We report a case of anterior auricular lymphadenitis caused by NTM in a healthy 41-year-old male adult. He was referred to the Department of Otolaryngology at Chiba University Hospital because of a mass in the front part of the right ear, which was suspected to be a parotid tumor. On initial examination, a 20-mm-sized, poorly mobile induration was felt under the right anterior ear skin. Ultrasonography revealed a mass with indistinct borders and irregular margins extending from near the capsule of the upper pole of the right parotid gland to the subcutaneous tissue. Magnetic resonance imaging showed contrast effect in the capsular portion, but a mass lesion was noted in the interior portion with little contrast effect. Puncture aspiration cytology showed no malignant findings, suggesting a granulomatous lesion with inflammation. Mycobacterial culture and polymerase chain reaction analysis of puncture specimens showed negative findings. On close examination, an abscess was observed, which burst naturally, and the pus was submitted for culture. Mass spectrometry and genetic analysis revealed Mycobacterium mageritense, rapidly growing mycobacteria, as the causative organism. Upon consulting with the Department of Infectious Diseases, the patient was started on drug therapy with sulfamethoxazole/trimethoprim and levofloxacin. However, after 2 months of treatment with the antimicrobial agent, the patient showed little improvement; therefore, we decided to perform surgical resection under local anesthesia. Pathological findings showed caseous epithelioid granulomas, suggestive of lymphadenitis caused by NTM. Treatment strategies for rapidly growing mycobacteria have not been established, and tailored treatment for individual cases need to be developed, considering the patients’ background, lesion status, and drug sensitivity.