Incidental mastoiditis on magnetic resonance imaging scans: clinical relevance and cost implications.

OBJECTIVES: To determine: (1) the incidence of incidental 'mastoiditis' reported on magnetic resonance imaging scans performed in patients with asymmetrical sensorineural hearing loss and/or unilateral tinnitus; (2) how many of those patients have actual otological pathology and/or require treatment; and (3) the financial implications of such a reporting practice. METHOD: Retrospective case series. RESULTS: Between October 2015 and November 2016, 500 patients underwent magnetic resonance imaging of the internal auditory meatus to rule out cerebellopontine angle lesions. There was an incidental finding of increased mastoid signalling in 5.8 per cent (n = 29), of which 20.7 per cent (6 of 29) were reported as bilateral cases. The diagnosis of 'mastoiditis' was found in 39.7 per cent (29 of 73). None of these patients had any pathology identified clinically. Other significant pathology was identified in a further 8.8 per cent (n = 44). CONCLUSION: The diagnosis of mastoiditis is primarily clinical. An incidental finding of high signalling in the mastoid region on magnetic resonance imaging is highly unlikely to represent actual clinical disease. In patients who are scanned for other reasons and who do not complain of otological symptoms, such findings are unlikely to require otolaryngology input.

Significance of the Hygiene Charter towards different sectors in Hong Kong.

The occurrence of SARS in March 2003 has resulted in an increased interest, worldwide in emerging infectious diseases. The SARS experience provided us a lesson on the importance of promoting hygienic practices among individuals and different working sectors. In Hong Kong, a voluntary organization called the UNITE proposed a Hygiene Charter which aimed at taking hygiene to new levels. This action has been supported by individuals and different sectors including the Personal and Family, Management, Buildings, Catering, Education, Finance and Commercial, Industrial, Medical and Health, Public Transportation, Social Welfare, Sports and Culture and Tourism. As promotion and maintenance of environmental health requires input from different sectors, the signing of the Hygiene Charter provides an opportunity for individuals and the public to show their pledge and commitment to good hygiene practices. As a result, with environment improvement and good infectious disease control measures, prevention of epidemics of infectious diseases is deemed to be possible.

Processing of DNase domain during translocation of colicin E7 across the membrane of Escherichia coli.

Translocation of colicin across the membrane of sensitive cells has been studied extensively. However, processing of the toxicity domain of colicin during translocation has been the subject of much controversy. To investigate the final translocation product of colicin across the membrane of Escherichia coli, an endogenously expressed His-tagged Im7 protein was constructed to detect any translocation product containing the DNase domain traversed the inner membrane into cytoplasm of the E. coli cells. As a result, a final processed DNase domain of ColE7 was identified in the intracellular space of the cells treated with Col-Im complex. In the presence of periplasmic extracts, in vitro processing of DNase domain of ColE7 was also observed. These results suggest that the processing of ColE7 has occurred for translocation of the DNase-type colicin across the membrane and the process is probably taking place in the periplasmic space of the membrane.