Biomedical subjects

R Cunningham

Publications and source records attributed to R Cunningham.

At least 163 records · Page 9Linked to original sources

PubMed1996

Once-daily gentamicin: translating theory into practice.

Gentamicin continues to have an important role in the treatment of serious bacterial infections. There is increasing interest in once-daily administration, which is more convenient than multiple-dose regimens. Animals studies and clinical trials suggest that once-daily administration is as efficacious and no more toxic for a variety of infections, but there is still some reluctance to use once-daily regimens routinely in neutropenic patients, because of the potential risk of breakthrough bacteraemia. A number of aspects of the serum concentration monitoring of once-daily gentamicin remain unresolved. The most commonly used assay systems are not sensitive enough, without some modification in technique, to detect the very small pre-dose concentrations seen with once-daily dosing, and it is not clear what constitutes an acceptable pre-dose concentration. Until the results from further studies become available, it is prudent to maintain a pre-dose concentration below 1 mg.1(-1), and local arrangements are necessary to address the frequency and timing of assays. It seems likely that once-daily administration will become the norm, because of its many advantages.

Animals↗

PubMed1996

Post-transplant renal artery stenosis: impact of therapy on long-term kidney function and blood pressure control.

PURPOSE: We assessed the long-term outcome of different treatment methods for transplant renal artery stenosis. MATERIALS AND METHODS: Outcome data for 23 patients with transplant renal artery stenosis treated during a 16-year period were reviewed and analyzed. RESULTS: There was a higher incidence of renal artery stenosis in cadaveric donor kidneys compared to living donor kidneys (2% versus 0.3%, p < 0.02), and in cadaveric kidneys from pediatric donors less than 5 years old compared to those from adults (13.2% versus 1.3%, p < 0.01). Six patients underwent primary medical treatment for renal artery stenosis, with a successful outcome in 4 (mean followup plus or minus standard error 57 +/- 22 months) and failure in 2. Of the patients 16 were treated with percutaneous transluminal angioplasty, including 12 who were cured or improved with respect to hypertension (followup 44.7 +/- 7.6 months). Five patients underwent surgical revascularization for renal artery stenosis with postoperative improvement of hypertension (followup 18.8 +/- 11.6 months). Overall, 21 of 23 patients (91%) were treated successfully for transplant renal artery stenosis with cure or improvement of associated hypertension. Posttreatment renal function was stable or improved in 18 patients, while renal function deteriorated due to parenchymal disease in 3. CONCLUSIONS: Most patients with transplant renal artery stenosis can be treated successfully. Percutaneous transluminal angioplasty is the initial interventive treatment of choice for high grade renal artery stenosis. Surgical revascularization is indicated if percutaneous transluminal angioplasty cannot be done or is unsuccessful.

Adult↗

PubMed1996

Air ambulance trauma transport: a quality review.

OBJECTIVE: Provincial air ambulance transports of injured patients were quality reviewed prospectively to determine utilization and appropriateness of care. METHODS: All trauma air ambulance transports over a 2-month span were reviewed prospectively. Revised Trauma Score, Injury Severity Score, probability of survival, prehospital time, distance of transport, procedures performed, and outcome were determined. Quality control questions were asked of the sending and receiving physicians. RESULTS: The majority of air ambulance transports reviewed (N = 97) were indicated for mechanism and severity of injury. Economics and requirement for advanced medical care were indications in only 15%. Physicians tended to perform more advanced procedures, likely related to higher patient Injury Severity Score (23 vs. 15, p = NS). Four problems with air ambulance access were identified. The overtriage rate was 5%. Inappropriate patient care was documented in six (6%) cases; a physician was present for only one of these. CONCLUSIONS: A low overtriage rate was documented, raising concerns that the undertriage rate may be too high. Injured patients air transported without physician accompaniment more often received inappropriate care, suggesting that physician accompaniment is beneficial.

Adult↗

PubMed1996

Clinical and molecular aspects of the pathogenesis of Staphylococcus aureus bone and joint infections.

Staphylococcus aureus is an important cause of bone and joint infections. In recent years, significant changes in the incidence of septic arthritis and osteomyelitis have occurred. Haematogenous osteomyelitis is now less common during childhood, but secondary spread of infection to bone or joint from a contiguous site in adults is increasing in incidence. Infection introduced at the time of surgery or arising by the haematogenous route is a significant complication of prosthetic joint implantation, and the effect of bone cement on local immune function may be important in this setting. ALthough S. epidermis is a more common cause of prosthetic joint infection, S. aureus is more difficult to treat. S. aureus produces a number of extracellular and cell-associated factors, but it is unclear what role these have as virulence factors in vivo. Furthermore, it is difficult in animal models to simulate transient bacteraemia followed by non-fulminating septic arthritis or osteomyelitis, as occurs in the patient. Surface factors which may be important in pathogenesis include the cell wall (activates complement and stimulates cytokine release), capsular polysaccharide (promotes adhesion to host cell surfaces), collagen receptors and fibronectin-binding protein. Staphylococcal toxic shock syndrome toxin (TSST-1) and the enterotoxins are superantigens and have the potential to suppress plasma cell differentiation and antibody responsiveness. TSST-1-positive isolates have been shown to cause more severe joint infection in one animal model, but most other studies to date have focused on in-vitro rather than in-vivo effects. There is little evidence supporting a role for coagulase, lipase and the haemolysins in staphylococcal bone and joint infections. Despite the clinical importance of these infections, surprisingly little is known about pathogenesis at the cellular level. Future research should focus on the role of the host immune system in limiting spread of infection, and the expression of virulence factors in animal or other models incorporating isogenic mutant strains.

Arthritis, Infectious↗

PubMed1996

An unusual cause of stress fracture of the first rib.

An unusual case of stress fracture of the first rib that occurred in a young male as a result of the constant loading due to carrying a heavy schoolbag is reported. This case demonstrates the difficulty in diagnosis and highlights the need for awareness of this condition, thus avoiding invasive investigation.

Adolescent↗

PubMed1996

Amphotericin B responsive Scedosporium apiospermum infection in a patient with acute myeloid leukaemia.

A 71 year old man with newly diagnosed acute myelomonocytic leukaemia developed a soft tissue infection of his foot during his first course of chemotherapy. Scedosporium apiospermum was isolated from the lesion, which resolved rapidly on treatment with intravenous amphotericin B despite being resistant in vitro to this agent. This observation suggests that sensitivity testing of S apiospermum should be interpreted with caution and that clinical response may be a better indicator of outcome.

Aged↗

PubMed1995