Reduced Host Defense Research Articles

Impaired granulocyte formylpeptide-induced superoxide generation in chronically ill, malnourished, elderly patients.

Protein-energy malnutrition (PEM), often occurring in patients with chronic disease, is associated with a decreased capacity to combat infections. In this study we assessed polymorphonuclear neutrophil (PMN) superoxide anion (*O2-) formation in elderly PEM patients with various chronic diseases. Nineteen patients (75+/-1 years), with body mass index 17.1+/-0.4, and 19 age-matched healthy controls were included. Fourteen patients and 14 controls were re-examined in a 3 month follow-up. A service of internal medicine at a university-affiliated hospital. Eight patients were prescribed a dietary liquid supplementation during the observation period. Superoxide production in PMN induced by fMLP (a receptor ligand) and phorbol myristate acetate (PMA), which acts directly on protein kinase C. fMLP-induced superoxide generation in the malnourished patients was 55+/-5% of that of the controls. However, the patients retained their capacity, 108+/-6% of control PMN generation, to respond to PMA. In those who received formula supplementation, fMLP-generated *O2- production levels were 48+/-8 and 73+/-13% (P = 0.12) of those of controls at the start and after 3 months, respectively. Corresponding figures in those who were not prescribed supplementation were 57+/-8 and 64+/-4% (P = 0.55). Possibly contributing to reduced host defence, receptor ligand-induced PMN generation of *O2 is significantly lower in chronically ill, elderly patients with PEM than in age-matched healthy controls.

Clinical Review of the Mechanism and Applications of Hyperbaric Oxygen Therapy in Small Animal Surgery

SummaryHyperbaric oxygen therapy has shown benefits both experimentally and clinically in human disease associated with vascular compromise and reduced host defenses. Potential benefits include the stimulation of leucocyte and macrophage function, increased oxygen availability for cellular function, stimulation of wound healing, and direct antibacterial effects. Similar applications may exist in veterinary medicine. This study documents 14 consecutive animals treated with hyperbaric oxygen, as an adjunct to standard therapy, for degloving injuries and/or skin grafts (n = 6), severe trauma (n = 3), compromised wound healing (n = 3), osteomyelitis (n = 1), and for anaerobic infection (n = 1). Subjectively, recovery was improved in these animals. If available, hyperbaric oxygen therapy deserves consideration as an adjunct to standard therapy for certain disorders.The potential benefits of hyperbaric oxygen therapy are discussed in the light of a study of 14 cases.

Patients with locally and generally reduced host defence

Patients with locally and generally reduced host defence

Aspergillus sinusitis in neutropenic patients with cancer : a review

Aspergillosis typically occurs in patients with reduced host defenses; such patients include renal and marrow recipients as well as patients with chemotherapy-induced myelosuppression. Pulmonary structures are most frequently involved; non-pulmonary involvement (including sinus) has not been frequently reported. In the present study, paranasal sinusitis occurred in 52 myelosuppressed cancer patients treated over 5 years at the UMCC with chemotherapy. Twenty-one patients had Aspergillus sinusitis; Aspergillus spp; including flavus and niger, were directly recovered from sinus in 19 of the 21 infections. Two other patients were considered clinically, although not microbiologically, documented. Multiple predisposing factors for Aspergillus sinusitis during the 60 days prior to infection diagnosis appear to exist; these include : 1) granulocyte count < 500 mm 3 (mean duration, 42 days versus 14 days for sinusitis of other etiology; P<0.001); 2) prolonged hospitalization (mean duration, 22 days versus 14 days for patients with non-fungal sinusitis; P<0.001); and 3) prolonged antibiotic therapy (mean duration, 22 days versus 9 days; P<0.001). The Aspergillus sinusitis resolved in 18 of 21 patients following treatment with amphotericin B; however, 11 of 18 patients had infection recurrence that always developed when tumor recurred and chemotherapy was reinstituted.

The relationship between oral health and systemic infections among elderly residents of chronic care facilities: a review.

Elderly residents living in chronic care facilities such as nursing homes and homes for the aged are more likely to become ill or die from lower respiratory tract infections and other systemic infections than age‐ and sex‐matched persons living in the community. Bacterial infections such as non‐pneumococcal pneumonia are responsible for a large proportion of the hospital admissions from nursing homes and are implicated in many of the deaths that follow hospitalization. The incidence of infection in this group can be attributed to a change in the host's defence mechanisms and to an increased exposure to pathogenic microorganisms. The intent of this review is to develop from evidence in the literature the hypothesis that poor oral hygiene among residents of chronic care facilities increases their exposure to microorganisms found in the oral cavity and, in combination with reduced host defence mechanisms, results in an increased incidence of systemic infections. It is proposed that preventive programs designed to limit oral infections will go far to reduce hospital admissions from chronic care facilities and even lower the mortality rate related specifically to systemic bacterial infections in these patients.

Cefotaxime therapy in children with serious infections associated with reduced host defense mechanisms

Thirty children were treated with cefotaxime (CTAX) in this study. The children suffered from respiratory tract infection (4), skin and soft tissue infection (4), infection of bones or joints (2), gastrointestinal infection (5), septicaemia (5), septicaemia and urinary tract infection (3), septicaemia and infection of the skin (3), septicaemia and infection of bones (2), urinary tract infection and infection of bones (1), enterocolitis (1). Nine out of these patients had leukaemia and 2 bone marrow aplasia. The dose of CTAX usually was 100 mg/kg/day. There were 25 cures and 4 failures and in one case assessment was impossible. Local tolerance of intravenous injection was good and no serious side-effects were reported.

Necrotizing fasciitis.

The author's experience of fourteen patients with necrotizing fasciitis is reviewed. The pathognomonic feature of this condition is an extensive necrosis of subcutaneous tissue caused by a vicious cycle of infection, local ischaemia and reduced host defence mechanisms. The diagnosis can only be confirmed by immediate exploratory incision. The reported mortality of 30-40% reflects the inadaquacy of conservative surgery in the treatment of this serious condition. Mortality can be reduced by early recognition followed by radical excision of the necrotic fascia and overlying skin. The preservation and subsequent use of the excised skin has the advantage of economy in the use of donor areas and reduction in morbidity. Hyperbaric oxygen therapy does not halt the spread of the necrotizing process and is not a substitute for radical surgery.