Infection with 2009 H1N1 influenza virus primes for immunological memory in human nose-associated lymphoid tissue, offering cross-reactive immunity to H1N1 and avian H5N1 viruses.

Influenza is a highly contagious mucosal infection in the respiratory tract. The 2009 pandemic H1N1 (pH1N1) influenza virus infection resulted in substantial morbidity and mortality in humans. Little is known on whether immunological memory develops following pH1N1 infection and whether it provides protection against other virus subtypes. An enzyme-linked immunosorbent spot assay was used to analyze hemagglutinin (HA)-specific memory B cell responses after virus antigen stimulation in nose-associated lymphoid tissues (NALT) from children and adults. Individuals with serological evidence of previous exposure to pH1N1 showed significant cross-reactive HA-specific memory B cell responses to pH1N1, seasonal H1N1 (sH1N1), and avian H5N1 (aH5N1) viruses upon pH1N1 virus stimulation. pH1N1 virus antigen elicited stronger cross-reactive memory B cell responses than sH1N1 virus. Intriguingly, aH5N1 virus also activated cross-reactive memory responses to sH1N1 and pH1N1 HAs in those who had previous pH1N1 exposure, and that correlated well with the memory response stimulated by pH1N1 virus antigen. These memory B cell responses resulted in cross-reactive neutralizing antibodies against sH1N1, 1918 H1N1, and aH5N1 viruses. The 2009 pH1N1 infection appeared to have primed human host with B cell memory in NALT that offers cross-protective mucosal immunity to not only H1N1 but also aH5N1 viruses. These findings may have important implications for future vaccination strategies against influenza. It will be important to induce and/or enhance such cross-protective mucosal memory B cells.

A simple and reliable predictor for an adequate laryngeal view with rigid endoscopic laryngoscopy.

OBJECTIVES: It is sometimes impossible to obtain an adequate laryngeal view during rigid endoscopic laryngoscopy. This may be due to a high tongue base. Our study seeks to determine a correlation between tongue base level and the adequacy of laryngeal view obtained with a 70-degree rigid endoscope. STUDY DESIGN AND SETTING: Over a period of 4 months, patients from a voice clinic were gathered and categorized into class I to III according to Mallampati et al (1985). Rigid laryngo-videostroboscopy was conducted to assess the larynx and the adequacy of the view was recorded. RESULTS: 74 patients were recruited. The number of adequate views were: class I = 18/20 (90%); class II = 20/33 (60.6%); class III = 7/21 (33.3%). chi 2 analysis demonstrated significance trend in all 3 classes. CONCLUSION: The level of the tongue base correlated well with the adequacy of laryngeal view obtained from a 70-degree rigid endoscope. This can be used to predict the success of obtaining adequate views during rigid laryngoscopy.

Nontuberculous mycobacterial adenitis: effectiveness of chemotherapy following incomplete excision.

BACKGROUND: Management of lymphadenopathy caused by nontuberculous mycobacteria (NTM) is primarily surgical. Where this cannot achieve sufficient clearance of infected nodes, chemotherapy is often given. AIM: This study compared results of surgery alone with surgery followed by chemotherapy in instances where there was incomplete surgical removal of diseased tissue. METHODS: Chemotherapy comprised azithromycin 10 mg/kg and rifabutin 6 mg/kg both given once daily for 6 mo. Ninety-eight children with NTM infection were seen in the period 1990-2004. Sixty-eight cases with adenopathy where "time to healing" (discharge stopped and inflammation settled) was known were available to compare response to treatment. RESULTS: The median (range) "time to healing" in weeks for 43 patients who had surgery alone was: incision and drainage (I&D)/curettage 6 (1-72) (n = 10); excision 3 (1-28) (n = 22); and from the last operation of multiple (repeat) surgery 3 (1-40) (n = 11). For 25 patients who required chemotherapy in addition to surgery, the median (range) "time to healing" in weeks was I&D/curettage 10 (1-40) (n = 17), excision 14 (8-20) (n = 2) and multiple surgery 29 (2-88) (n = 6). CONCLUSION: In children with adenitis due to NTM, where surgical resection is followed by continued discharge and inflammation, chemotherapy should be considered before further surgery is undertaken.