Biliary infection and bacteremia caused by beta-lactamase-positive, ampicillin-resistant Haemophilus influenzae in a diabetic patient

We report the case of a 73-year-old female patient with diabetic nephropathy and cholelithiasis. She was admitted to our hospital with right upper abdominal pain, nausea, and vomiting. The patient had visited an outpatient clinic with the same complaints 2 days earlier, and had been prescribed antibiotics empirically (two doses ofloxacin orally). Blood cultures taken before the start of antibiotic treatment in our hospital were negative. The patient was treated with parenteral ampicillin/sulbactam + ciprofloxacin empirically. The empiric antibiotic treatment was discontinued after 7 days. Elective cholecystectomy was performed after her general condition improved. An aerobic chocolate agar culture of the cholecystectomy material yielded Haemophilus influenzae type b. On postoperative day 3 the patient developed fever again. The fluids collected after cholecystectomy were evaluated microbiologically. H. influenzae type b was isolated from the samples and blood cultures. The patient was diagnosed with H. influenzae cholecystitis, and recovered after 10-day treatment with ampicillin/sulbactam + ciprofloxacin. The findings are discussed together with references for differential diagnosis. H. influenzae cholecystitis due to cholelithiasis, although rare, should be considered in elderly patients with a history of chronic diseases such as diabetes mellitus or nephropathy.     

Schwannoma of the conus medullaris: a rare case

Intradural schwannoma of the conus medullaris is a rare form of spinal neoplasm, which commonly occurs in the lumbar region. Conus medullaris level is unusual for schwannomas. A 49-year-old woman presented with chronic sciatica, mild bladder dysfunction, and paresthesia in the buttocks. Magnetic resonance imaging of the spine showed a mass lesion in the conus medullaris region with nerve compression. The tumor was completely resected and diagnosed histologically as schwannoma. The patient recovered after surgery. Clinical and radiologic features of this rare tumor are reviewed and are accompanied by literature findings.     

Outcomes of acute renal failure patients requiring intermittent hemodialysis

The published studies on the prognosis of patients requiring intermittent hemodialysis (IHD) are scarce and have some conflicts. In this study, we retrospectively analyzed our data on ARF patients who were treated with IHD. A total of 192 (female: 85, 44.3%; male: 107, 55.7%) patients were included in the study. The mean age was 56.3 +/- 17.1 years. In all, 48.9% of the patients were older than 60 years. The mean number of IHD sessions was 7.8 +/- 8.0 per patient; 12.4% was due to prerenal causes, 76.8% was due to intrarenal causes, and 10.8% was due to postrenal causes. The leading indication of the IHD was uremic symptoms (46.8%). With the exclusion of hypertension, 72.4% of the patients had at least one systemic comorbidity. After treatment, 75.5% of the patients recovered, in contrast to 9.4% of patients who were transferred to chronic renal replacement programs and 15.1% who died during IHD period. Pre-dialytic serum creatinine (p = 0.003) and albumin levels (p = 0.016), total IHD session number per patient (p = 0.003), and age (p = 0.034) were the parameters that were related to high mortality in statistical analysis. Mortality was higher if the leading indication of IHD was biochemical disturbances (p = 0.013). Diabetes mellitus did not influence mortality. Consequently, predialytic serum creatinine and albumin levels may be very important predictors of mortality. Patients in high-risk groups (older age, female sex, and low pre-dialytic creatinine and albumin levels) should be considered to be treated with slow continuous renal replacement methods.     

Amikacin-induced nephropathy: is there any protective way?

Amikacin is a commonly used antibacterial drug that can cause significant nephrotoxic effects in both humans and experimental animals. It has been reported that one mechanism of the toxic effects of aminoglycoside antibiotics are the result of oxidative reactions. The aim of this study is to examine the effects of N-acetylcysteine, a thiol-containing antioxidant, on renal function (serum creatinine) and morphology (renal tubular damage) in mice subjected to amikacin-induced nephrotoxicity. A total of 32 mice were equally divided into four groups that were injected with either saline, amikacin (1.2 g/kg intraperitoneally), N-acetylcysteine (150 mg/kg intraperitoneally for three days) plus amikacin (1.2 g/kg intraperitoneally on the third day as a single dose), or N-acetylcysteine (150 mg/kg intraperitoneally). Amikacin administration led to granulovacuolar tubular degeneration in light microscopic examination and myeloid bodies, mitochondrial electron-dense material deposition, and mitochondrial swelling in the proximal tubule epithelium in the electron microscopic evaluation. N-acetylcysteine administration before amikacin injection caused significant decreases in myeloid body and mitochondrial swelling and granulovacuolar tubular degeneration formation. Serum creatinine levels did not change as a result of any treatment. The results show that N-acetylcysteine has a protective effect on nephrotoxicity induced by amikacin. Higher doses of amikacin should be tried to observe biochemical effects.     

An unusual etiology of erythropoietin resistance: hyperthyroidism

Many possible causes of resistance to human recombinant erythropoietin (rh-EPO) have been reported in patients with renal failure. This case presents an unusual cause of erythropoietin-resistant anemia in a patient with chronic renal failure. A 61-year-old male patient who was on chronic hemodialysis program due to diabetic nephropathy for seven months developed erythropoietin resistant anemia. No iron deficiency was revealed by laboratory data, no megaloblastic anemia were found by biochemical investigation, and no inflammatory states including infection or neoplastic diseases were disclosed by abdominal ultrasonography, chest X-ray, bone marrow aspiration and biopsy, or other methods (normal C-reactive protein levels). This hemodialysis patient had epoetin-resistant anemia with primary autoimmune hyperthyroidism. The anti-thyroid therapy was effective not only against the hyperthyroidism but also against his epoetin resistant anemia.     

Hyperbaric oxygen therapy reduces the severity of necrotizing enterocolitis in a neonatal rat model

Introduction

Hyperbaric oxygen (HBO) therapy is known to increase oxygen concentration in tissues leading to induction of an adaptive increase in antioxidants, stimulation of angiogenesis, improvement of white blood cell action, and regulation of inflammatory process. Therefore, we tested the potential beneficial effect of HBO in neonatal rat model of necrotizing enterocolitis (NEC).

Materials and Methods

Thirty newborn Sprague-Dawley rats, provided by the Experimental Research Council, Gulhane Military Medical Academy, Ankara,Turkey, were randomly divided into 3 groups as follows: NEC, NEC + HBO, and control. Necrotizing enterocolitis was induced by enteral formula feeding and exposure to hypoxia after cold stress at 4°C and oxygen. The NEC + HBO group received HBO at 2.8 atmosphere absolute (ATA) for 90 minutes daily for 3 days. The pups were killed on the fourth day, and their intestinal tissues were harvested for biochemical and histopathologic analysis. Blood samples were also obtained from the pups.

Results

The mortality rate was highest in the NEC group (3 pups in the NEC group vs 1 pup in the NEC + HBO group). Malondialdehyde and protein carbonyl content were significantly increased, whereas superoxide dismutase and glutathione peroxidase were significantly decreased in the NEC group. All these changes were similar to control levels in the NEC group by HBO treatment. Nitrate plus nitrite (NO_x) levels and serum tumor necrosis factor α were increased in the NEC group and histopathologic injury score and apoptosis index in the NEC group were significantly higher than in the NEC + HBO group.

Conclusion

Hyperbaric oxygen significantly reduced the severity of NEC in our study.     

Antioxidant effects of melatonin in rats during chronic exposure to hyperbaric oxygen

In addition to its beneficial effects, hyperbaric oxygen (HBO) exposure causes some detrimental effects via oxidative stress. Previous experimental studies showed that melatonin is a useful agent to block single session HBO-induced oxidative stress. In the present study, we investigated the antioxidant effect of exogenously administered as well as endogenously produced melatonin in lung and brain tissues of rats exposed to long term HBO. The HBO procedure was set as daily exposures to 2.5 ATA of oxygen for 1 hr and a total of 10 sessions. Twenty-eight male Sprague-Dawley rats were divided into four groups as follows: control, daytime HBO, daytime HBO plus melatonin (5 mg/kg), nighttime HBO. Tissue oxidative/antioxidant status was examined by determining the protein carbonyl content as a criteria for oxidative stress and the activities of the antioxidant enzymes, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). HBO exposure for 10 days caused significant increases in protein carbonyl content and SOD levels of lung and brain, but GSH-Px activities remained unaffected. The increases in protein carbonyls were blocked by exogenously administered melatonin and in part by nighttime exposure to darkness whereas the increase of SOD activity was only impeded by endogenously produced melatonin in brain tissue. Lung SOD activity was augmented by endogenous melatonin. In conclusion, melatonin blocks long-term HBO-induced cumulative oxidative stress as indicated changes in protein carbonyls. Both exogenously injected and physiologically secreted melatonin has this potential. The effects of HBO-exposure and melatonin on the activities of the antioxidative enzymes are less clear.