Search

Background Beginning from late 2011 and early 2012, increasing circulation of antigenically drifted influenza A/Victoria/361/2011-like H3N2 viruses within genotype 3 of the A/Victoria/208/2009 clade have been reported in multiple European countries and elsewhere. Whether these emerging viruses are associated with increased disease severity is unclear. Objectives To report the clinical and virological findings of a moderately severe hospital outbreak of A/Victoria/361/2011-like viruses that occurred in November 2011 in Hong Kong. Study design Clinical and virological hospital outbreak investigation. Results The outbreak occurred in an adult psychiatric ward in November 2011, a time well before the usual local seasonal influenza winter peak. Altogether, 7 patients and 1 healthcare-worker were affected (mean age, 47 [range, 34–61] years). The attack rates among patients and healthcare-workers were 33% (7/21) and 7% (1/15), respectively. Pneumonia developed in 38% (3/8) of cases; none had underlying immunocompromised conditions. High nasopharyngeal viral loads were detected. All cases responded to antiviral treatment. Multiple amino acid mutations with reference to earlier A(H3N2) vaccine strains were mapped to key antigenic sites on hemagglutinin; however, no critical mutations on receptor binding sites were detected. Viral sequence variations jeopardized the performance of molecular diagnostic assays. Conclusions Severe disease and pneumonia occurred in a substantial proportion of non-immunocompromised adults in a hospital outbreak attributed to the emerging antigenically drifted A/Victoria/361/2011-like H3N2 viruses. Close monitoring of the transmission of this drift variant is required. Further studies are also necessary to determine virus virulence.

In May 1996, a 56-year-old man in Hong Kong presented with fever and dry cough and had miliary shadows in bilateral lung fields on chest radiographs. The patient had migrated from Shanghai more than 10 years previously and worked as a cook. Upon admission, he was also found to have diabetes with poor glycaemic control. The clinical diagnosis was miliary tuberculosis (TB), however, all mycobacterial cultures were negative. The man was put on empirical anti-tuberculosis medication. Thrombocytopenia developed shortly afterwards. Bone marrow biopsy revealed foci of epithelioid cell granuloma and normal haematopoiesis, consistent with tuberculosis. Four months later, he presented with persistent bilateral epididymal masses with scrotal pain for 2 weeks. Tender and hardened epididymes were found upon physical examination. The clinical diagnosis was TB epididymitis. Mycobacterial culture of his early morning urine was negative. The empirical anti-TB treatment was lengthened to a total of 18 months until November 1997. In 1998, an incidental finding of bilateral adrenal masses was noted upon computed tomography (CT) of his abdomen. These masses were of soft tissue consistency density with no contrast enhancement in early and delayed phases. CT-guided fine needle aspiration of the right adrenal mass revealed necrotic tissue only in two successive examinations. Ziehl–Neelsen (ZN) stain was negative. Follow-up CT scans indicated no significant interval change in the size of the masses. In 2002, the man complained of insidious onset of left shoulder pain and swelling, as well as knee pain. Magnetic resonance imaging (MRI) and arthroscopy of the left shoulder were performed. MRI revealed rice bodies distending the joint capsule, especially over the subcoracoid and subdeltoid bursae. The clinical diagnosis was TB arthritis and osteomyelitis. Histology of the synovectomy specimen showed oedematous tissue with moderate chronic inflammation and a small focus of granulomatous inflammation. Neither caseous necrosis nor multinucleated giant cell was noted. ZN stain was again negative. The bacterial and mycobacterial cultures of the left shoulder synovial tissue and left knee aspirate were negative. No anti-TB treatment was prescribed. In January 2004, the man presented with significant weight loss. Workup revealed elevated alpha-fetoprotein. A liver tumour was detected, measuring 60640630 mm in greatest dimension and occupying the right lobe of liver, associated with unresolved bilateral adrenal enlargement. A short Synacthen test confirmed normal hypothalamic-pituitary-adrenal function. Partial hepatectomy (central), right adrenalectomy and cholescystectomy were performed. The right adrenal gland measured 55635618 mm in size and weighed 15 g. Serial sectioning showed a nodule with necrotic yellowish material (Fig. 1). Figures 2A and B show the H&E and Grocott stains of the sections of the adrenal lesion, respectively.

(2005). Myiasis by Chrysomya bezziana in surgical pathology. Pathology: Vol. 37, No. 1, pp. 80-82.