Urticaria is a skin disease characterised by short-lived surface swellings of the dermis (wheals) frequently accompanied by itching. It is classified as acute or chronic depending on whether the wheal recurrence occurs for less or more than six weeks. Acute urticaria is often due to a hypersensitivity reaction, whereas about 50% of the cases of chronic urticaria are regarded as autoimmune.

Urticaria may occur alone or in association with a deeper swelling (angioedema) involving the subcutaneous and/or submucosal tissues, and last from hours to a few days. Angioedema can also develop alone, and may be idiopathic or be caused by allergies, inherited or acquired deficiencies of C1-inhibitor protein, or adverse drug reactions. An interplay between inflammation and coagulation has been proposed as a pathomechanism in urticaria and urticaria-associated angioedema (in which histamine and thrombin are involved), as well as in angioedema due to C1-inhibitor deficiency, which involves various biological systems. An increase in the plasma markers of thrombin generation, fibrinolysis and inflammation has been documented during exacerbations of urticaria and angioedema, with the marker levels decreasing to normal during remission. However, the hypercoagulable state in chronic urticaria and angioedema has not been reported to be associated with any increased risk of thrombosis, although there have been a number of reports of cardiovascular events occurring during episodes of acute urticaria.

These observations have provided the rationale for the clinical evaluation of anticoagulant and antifibrinolytic drugs, the efficacy of which has sometimes been demonstrated.

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Anaphylaxis is a rare adverse event following immunisation (AEFI) and unlikely to be detected in prelicensure vaccine trials. Previous retrospective studies have been hampered by the paucity of information available to passive reporting schemes.

The aim of the present study was to estimate the incidence and clinical presentation of anaphylaxis as an AEFI using prospective active surveillance.

Methods : Children under 16 in the UK and Ireland with suspected anaphylaxis as an AEFI were reported through the British Paediatric Surveillance Unit (BPSU) between September 2008 and October 2009. Paediatricians completed questionnaires on presentation, diagnosis, management and outcome.

Results : A total of 7 out of 15 reports met criteria for anaphylaxis following immunisation. Four of the seven children reacted more than 30 min after administration of the vaccine. Six children required treatment with intramuscular adrenaline and intravenous fluids, but all made a full recovery. Denominators were not available for all vaccines so an overall incidence was not calculated, however the estimated incidence was 12.0 per 100 000 dose for single component measles vaccine and 1.4 cases per million doses for the bivalent human papilloma virus vaccine (Cervarix, GSK).

Conclusions : Anaphylaxis remains a rare adverse event following immunisation. No cases were related to vaccines given as part of the 'routine' infant and preschool immunisation programme, despite over 5.5 million vaccines being delivered in this time period. Some children had delayed onset of symptoms and this should be considered when vaccinating those at higher risk of anaphylaxis.

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A wide spectrum of thoracic tumors have known or suspected viral etiologies. Oncogenic viruses can be classified by the type of genomic material they contain. Neoplastic conditions found to have viral etiologies include post-transplant lymphoproliferative disease, lymphoid granulomatosis, Kaposi's sarcoma, Castleman's disease, recurrent respiratory papillomatosis, lung cancer, malignant mesothelioma, leukemia and lymphomas.

Viruses involved in these conditions include Epstein-Barr virus, human herpes virus 8, human papillomavirus, Simian virus 40, human immunodeficiency virus, and Human T-lymphotropic virus. Imaging findings, epidemiology and mechanism of transmission for these diseases are reviewed in detail to gain a more thorough appreciation of disease pathophysiology for the chest radiologist.

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It is well known that pulmonary tuberculosis is associated with an increased risk of lung cancer. We investigated whether a history of pulmonary tuberculosis is an independent risk factor for lung cancer survival in Caucasian patients.

METHODS: The data of the prospective population-based cohort of The Rotterdam Study were used. During a mean follow-up time of 18 years, there were 214 incident cases of pathology-proven lung cancer in a source population of 7983 study participants. History of tuberculosis was assessed at baseline by interviewers using standardized questionnaires. Associations of lung cancer survival with the occurrence of pulmonary tuberculosis were assessed using Cox's proportional hazard regression analysis adjusted for age, gender, pack-years, educational level and tumor stage.

RESULTS: A history of tuberculosis was reported in 13 of the 214 subjects with lung cancer. The survival of patients with lung cancer was significantly shorter in subjects with a history of pulmonary tuberculosis (HR=2.36, CI95%: 1.1-4.9), than in subjects without a history of pulmonary tuberculosis with a mean difference of 311 days.

CONCLUSION: The presence of a history of pulmonary tuberculosis may be an important prognostic factor in the survival of lung cancer.

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