Treatment of visceral leishmaniasis

The available treatment options for visceral leishmaniasis (VL) have problems relating to efficacy, adverse effects and cost, making treatment a complex issue. We review the evidence relating to the different methods of treatment in relation to - efficacy and toxicity of the drugs in different areas of the world; ability to monitor side effects, length of treatment; ability of patients to pay for and stay safe during treatment, ability of the healthcare services to give intramuscular, intravenous or oral therapy; the sex and child-bearing potential of the patient and the immune status of the patient. The high mortality of untreated/ poorly treated VL infection makes the decisions paramount, but a unified and coordinated response by each area is likely to be more effective and informative to future policies than an ad hoc response. For patients in resource-rich countries, liposomal amphotericin B appears to be the optimal treatment. In South Asia, miltefosine is being used; the combination of single dose liposomal amphotericin B and short course miltefosine looks encouraging but has the problem of potential reproductive toxicities in females. In Africa, the evidence to switch from SSG is not yet compelling. The need to monitor and plan for evolving drug failure, secondary to leishmania parasite resistance, is paramount. With a few drugs the options may be limited; however, we await key ongoing trials in both Africa and India to explore the effects of combination treatment. If safe and reliable combinations are revealed by the ongoing studies, it is far from clear as to whether this will avoid leishmania parasite resistance. The development of new drugs to add to the armamentarium is paramount. Lessons can be learnt from the management of diseases such as tuberculosis and malaria in terms of planning the switch to combination treatment. As important as establishing the best choice for specific antileishmanial agent is ensuring treatment centers, which can best manage the problems encountered during treatment, specifically malnutrition, bleeding, intercurrent infections, drug side effects and detecting and treating underlying immunosuppression.

Erythropoietin as a novel brain and kidney protective agent

Erythropoietin is a 30.4 kDa glycoprotein produced by the kidney, which is mostly known for its physiological function in regulating red blood cell production in the bone marrow Accumulating evidence, however suggests that erythropoietin has additional organ protective effects, which may specifically be useful in protecting the brain and kidneys from injury. Experimental evidence suggests that these protective mechanisms are multi-factorial in nature and may include inhibition of apoptotic cell death, stimulation of cellular regeneration, inhibition of deleterious pathways and promotion of recovery. In this article we review the physiology of erythropoietin, assess previous work that supports the role of erythropoietin as a general tissue protective agent and explain the mechanisms by which it may achieve this tissue protective effect. We then focus on specific laboratory and clinical data that suggest that erythropoietin has a strong brain protective and kidney protective effect. In addition, we comment on the implications of these studies for clinicians at the bedside and for researchers designing controlled trials to further elucidate the true clinical utility of erythropoietin as a neuroprotective and nephroprotective agent. Finally, we describe EPO-TBI, a double-blinded multi-centre randomised controlled trial involving the authors that is being conducted to investigate the organ protective effects of erythropoietin on the brain, and also assesses its effect on the kidneys.

Preoperative Estimated Glomerular Filtration Rate and RIFLE-Classified Postoperative Acute Kidney Injury Predict Length of Stay Post-Coronary Bypass Surgery in an Australian Setting

We investigated the influence of preoperative estimated glomerular filtration rate and postoperative acute kidney injury on outcomes after coronary bypass surgery in a local setting, with the focus on length of stay.

A retrospective analysis of prospectively collected data for 3302 consecutive patients who underwent coronary artery bypass graft surgery (June 1997 through to January 2007) at St Vincent's Public Hospital, Melbourne, was undertaken. Preoperative estimated glomerular filtration rate was calculated and categorised using US National Kidney Foundation cut-offs for chronic kidney disease (normal function; mild, moderate and severe dysfunction). Postoperative acute kidney injury was categorised using serum creatinine RIFLE criteria (no acute kidney injury, risk, injury and failure). Postoperative intensive care and hospital length of stay was determined.

The hazard ratios for time to hospital discharge up to one month decreased (indicating a longer length of stay) as severity of preoperative renal dysfunction category increased when compared to those with normal renal function: mild hazard ratio=1.02 (95% confidence interval: 0.91 to 1.15, P=0.70), moderate 0.87 (0.76 to 1.00, P=0.047), severe 0.47 (0.35 to 0.64, P < 0.001). Hazard ratios also decreased as severity of postoperative acute kidney injury category increased, when compared to those with no acute kidney injury: risk 0.67 (0.58 to 0.77, P <0.001), injury 0.52 (0.41 to 0.65, P <0.001), failure 0.35 (0.20 to 0.60, P <0.001).

The increasing severity of preoperative renal dysfunction and postoperative acute kidney injury were associated with increased hospital length of stay. This has implications for resource use, informed consent and case selection.

SPAMM, cine phase contrast imaging and fast spin-echo T2-weighted imaging in the study of intracranial cerebrospinal fluid (CSF) flow

AIM

To compare the qualitative assessment of cerebrospinal fluid (CSF) flow using a SPAMM (spatial modulation of magnetization) technique with cine phase contrast images (cine PC) and fast spin echo (FSE) T2-weighted images.

MATERIALS AND METHODS

SPAMM, PC and T2-weighted sequences were performed on 22 occasions in 19 patients. Eleven of the studies were performed following a neuroendoscopic third ventriculostomy (NTV), and in these cases, the success of the NTV was determined by clinical follow-up. Two observers used consensus to grade the presence of CSF flow at nine different sites for each study.

RESULTS

At 14 of the 178 matched sites, which could be assessed by both SPAMM and cine PC, SPAMM CSF flow grade was higher than that of cine PC. At a further 14/178 matched sites, the cine PC grade was higher than that of SPAMM. There was definite CSF flow at 113/182 (62%) of all the cine PC sites assessed, and 110/181 (61%) of all SPAMM sites assessed whilst 108/198 (54%) of FSE T2-weighted image sites demonstrated flow voids. Cine PC grades were higher than SPAMM at the cerebral aqueduct (P < 0.05, Wilcoxon sign rank test). Definite CSF flow within the anterior third ventricle was present in 4/5 (SPAMM) and 3/5 (cine PC) successful NTVs, 0/2 (SPAMM and cine PC) unsuccessful NTVs and 1/10 (SPAMM and cine PC) patients without NTV.

CONCLUSION

SPAMM provides a comparable assessment of intracranial CSF flow to that of cine phase contrast imaging at all CSF sites except the cerebral aqueduct.

Yield of mammography in selected patients age < or = 30 years

BACKGROUND

An outcomes analysis study was performed to quantify the benefit of directed diagnostic imaging of selected very young women (defined as < or = 30 years of age) in our population. Summary results are presented.

PATIENTS AND METHODS

Women's Imaging Services were queried for studies performed between April 1, 1997 and December 31, 1998 on women < or = 30 years of age. The authors' referral pathway mandates breast examination by a general surgeon or by the head of Women's Imaging before mammography in all such patients. Studies were excluded if there were reviews of scans performed at other sites. The resulting 142 mammograms were evaluated.

RESULTS

Ninety percent of the 142 studies were within normal limits. Only 11 mammograms indicated any required action (7.8%), and only 5 of these merited biopsy. All biopsies revealed benign disease. No carcinomas were detected by biopsy or on clinical follow-up in this cohort of women. These values are congruent with the scarce literature on mammography in this population.

CONCLUSIONS

The yield of mammography in the age < or = 30 years population is low.

Rectal bleeding after radiation therapy for prostate cancer: endoscopic evaluation

PURPOSE

To analyze the frequency and clinical importance of proctitis and hematochezia after radiation therapy for prostate cancer.

MATERIALS AND METHODS

Of 63 patients with prostate cancer treated with curative intent by a single radiation oncologist between July 1, 1993, and December 31, 1997, 30 were asymptomatic, but 33 had heme-positive digital rectal examination (DRE) results or hematochezia at routine follow-up. Twenty-six of these patients underwent endoscopy of the sigmoid colon or colon for evaluation of these symptoms. Median doses of 60.0 Gy at postoperative radiation therapy and 68.4 Gy at definitive radiation therapy were delivered to four fields daily by using blocking customized on the basis of computed tomographically documented evidence of disease. The Fisher exact test and the Kaplan-Meier method were used to analyze the results.

RESULTS

The frequency of rectal bleeding approached 80% at 3 years after radiation therapy in definitively treated patients. Only 14 patients had proctitis: eight as the only sign, and six in association with other disease. Six patients had other disease without proctitis, and four patients had normal examination findings. The frequency of rectal bleeding in the presence of proctitis was similar to that in the presence of other disease (Fisher exact test, P =.68).

CONCLUSION

Hematochezia or positive DRE findings are frequent sequelae of definitive radiation therapy for prostate cancer; however, causes other than proctitis are often documented at endoscopy. Symptomatic individuals warrant rigorous evaluation to rule out serious coexistent disease.

Differentiation of bronchogenic carcinoma from postobstructive pneumonitis by magnetic resonance imaging: histopathologic correlation

Obstructive pneumonitis frequently occurs distal to hilar bronchogenic carcinomas or in lung adjacent to peripheral tumors. The article evaluates the role of MRI in the differentiation of tumor from pneumonitis. Twelve patients underwent MRI of the thorax before surgery. T1-weighted (SE 310/20) and T2-weighted (SE 2000/60-120) images were obtained through the tumor and presumed areas of pneumonitis. Five histologic types of pneumonitis were identified on pathologic examination of the 12 specimens. Cholesterol pneumonitis, found in 7 patients, was the most common type. Organizing pneumonitis, bronchiectasis with mucus plugs, atelectasis, and abscess were found in 3, 4, 2, and 1 patients, respectively. MRI was able to differentiate tumor from pneumonitis in 5 of 6 patients with a hilar mass and in 5 of 6 patients with a peripheral tumor. This was achieved by a visual difference in signal intensity on heavily T2-weighted (SE 2000/120) images. Cholesterol pneumonitis and bronchiectasis with mucus plugs were always hyperintense relative to tumor, and organizing pneumonitis and atelectasis were isointense and indistinguishable from tumor. MRI can differentiate tumor from pneumonitis provided that pneumonitis is of the cholesterol type or if there are mucus plugs in the collapsed lung.

Lateral gaze deficit suggesting multiple sclerosis

The case of a 26-year-old white man with multiple sclerosis is presented. Although the patient was unaware of his condition, the signs and symptoms that he presented were highly suggestive of multiple sclerosis. The case is unusual in that initial diagnosis was made by a senior dental student in a social rather than a clinical setting and without a presenting complaint by the patient. The significance of a thorough clinical examination and the responsibility of a general practitioner as a primary health provider to be observant of signs of disease such as multiple sclerosis are discussed.

Reticulocyte size in nutritional anemias

Alterations in reticulocyte size occur 2-3 days after the onset of iron deficient or megaloblastic erythropoiesis and precede, by several weeks, changes in mean corpuscular volume (MCV). Iron-deficiency anemia induced in a normal subject by repeated phlebotomies was characterized by the initial development of larger than normal reticulocytes followed by an abrupt decrease in reticulocyte size. Microreticulocytes appeared 3 days after the fall in per cent iron saturation and antedated the decrease in MCV to below normal by 6 wk. Mean reticulocyte size was disproportionately smaller than normal in patients presenting with iron deficiency. In contrast, reticulocyte size increased abruptly in a patient (and rats) 2-3 days after administration of methotrexate. Mean reticulocyte size was disproportionately larger than normal in patients presenting with folate or vitamin B12 deficiency. Specific replacement therapy with iron, folate, or vitamin B12 was quickly followed by normalization of reticulocyte size.