Co-existing conditions for deaths from infectious and parasitic diseases in Australia

Objective: To examine the frequency distribution of co-existing conditions for deaths where the underlying cause was infectious and parasitic diseases. Materials and methods: Besides the underlying cause of death, the distributions of co-existing conditions for deaths from infectious and parasitic diseases were examined in total and by various age and sex groups, at individual and chapter levels, using 1998 Australian mortality data. Results: In addition to the underlying cause of death, the average number of reported co-existing conditions for a single infectious and parasitic death was 1.62. The most common co-existing conditions were respiratory failure, acute renal failure non-specific causes, ischaemic heart disease, pneumonia and diabetes. When studying the distribution of co-existing conditions at the ICD-9 chapter level, it was found that the circulatory system diseases were the most important. There was an increasing trend in the number of reported co-existing conditions from 60 years of age upwards. Gender differences existed in the frequency of some reported co-existing conditions. The most common organism types of co-existing conditions were other bacterial infection and other viruses. Conclusions: The study indicated that the quality of death certificates is less than satisfactory for the 1998 Australian mortality data. The findings may be helpful in clarifying the ICD coding rules and the development of disease prevention strategies. (C) 2003 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Steatosis: Co-factor in other liver diseases

The prevalence of fatty liver is rising in association with the global increase in obesity and type 2 diabetes. In the past, simple steatosis was regarded as benign, but the presence of another liver disease may provide a synergistic combination of steatosis, cellular adaptation, and oxidative damage that aggravates liver injury. In this review, a major focus is on the role of steatosis as a co-factor in chronic hepatitis C (HCV), where the mechanisms promoting fibrosis and the effect of weight reduction in minimizing liver injury have been most widely studied. Steatosis, obesity, and associated metabolic factors may also modulate the response to alcohol- and drug-induced liver disease and may be risk factors for the development of hepatocellular cancer. The pathogenesis of injury in obesity-related fatty liver disease involves a number of pathways, which are currently under investigation. Enhanced oxidative stress, increased susceptibility to apoptosis, and a dysregulated response to cellular injury have been implicated, and other components of the metabolic syndrome such as hyperinsulinernia and hyperglycemia are likely to have a role. Fibrosis also may be increased as a by-product of altered hepatocyte regeneration and activation of bipotential hepatic progenitor cells. In conclusion, active management of obesity and a reduction in steatosis may improve liver injury and decrease the progression of fibrosis.

Zinc and vitamin A supplementation in Indigenous Australian children hospitalised with lower respiratory tract infection: a randomised controlled trial

Objective: To evaluate the efficacy of supplementation with zinc and vitamin A in Indigenous children hospitalised with acute lower respiratory infection (ALRI). Design: Randomised controlled, 2-by-2 factorial trial of supplementation with zinc and vitamin A. Setting and participants: 187 Indigenous children aged < 11 years hospitalised with 215 ALRI episodes at Alice Springs Hospital (April 2001 to July 2002). Interventions: Vitamin A was administered on Days 1 and 5 of admission at a dose of 50 000 IU (infants under 12 months), or 100 000 IU; and zinc sulfate was administered daily for 5 days at a daily dose of 20 mg (infants under 12 months) or 40 mg. Main outcome measure: Time to clinical recovery from fever and tachypnoea, duration of hospitalisation, and readmission for ALRI within 120 days. Results: There was no clinical benefit of supplementation with vitamin A, zinc or the two combined, with no significant difference between zinc and no-zinc, vitamin A and no-vitamin A or zinc + vitamin A and placebo groups in time to resolution of fever or tachypnoea, or duration of hospitalisation. Instead, we found increased morbidity; children given zinc had increased risk of readmission for ALRI within 120 days (relative risk, 2.4; 95% CI, 1.003–6.1). Conclusion: This study does not support the use of vitamin A or zinc supplementation in the management of ALRI requiring hospitalisation in Indigenous children living in remote areas. Even in populations with high rates of ALRI and poor living conditions, vitamin A and zinc therapy may not be useful. The effect of supplementation may depend on the prevalence of deficiency of these micronutrients in the population.

Perspective on the host response to human metapneumovirus infection: what can we learn from respiratory syncytial virus infections?

Human metapneumovirus (HMPV) is a recently discovered pathogen first identified in respiratory specimens from young children suffering from clinical respiratory syndromes ranging from mild to severe lower respiratory tract illness. HMPV has worldwide prevalence, and is a leading cause of respiratory tract infection in the first years of life, with a spectrum of disease similar to respiratory syncytial virus (RSV). The disease burden associated with HMPV infection has not been fully elucidated; however, studies indicate that HMPV may cause upper or lower respiratory tract illness in patients between ages 2 months and 87 years, may co-circulate with RSV, and HMPV infection may be associated with asthma exacerbation. The mechanisms and effector pathways contributing to immunity or disease pathogenesis following infection are not fully understood; however, given the clinical significance of HMPV, there is a need for a fundamental understanding of the immune and pathophysiological processes that occur following infection to provide the foundation necessary for the development of effective vaccine or therapeutic intervention strategies. This review provides a current perspective on the processes associated with HMPV infection, immunity, and disease pathogenesis. (c) 2005 Elsevier SAS. All rights reserved.