van der Knaap's leukoencephalopathy: report of five new cases with emphasis on diffusion-weighted MRI findings

We present five new cases of van der Knaap's leukoencephalopathy, which is a rare abnormality characterized by infantile-onset white matter disease with swelling and mild clinical course. Based on the very rare histopathological data, this disease is considered a vacuolating myelinopathy with peripherally located intralamellar vacuoli. Although approximately 70 cases have so far been published, there are very limited data in the literature regarding diffusion-weighted imaging (DWI) findings of this recently discovered entity. In this paper, in addition to MRI, MRS and DWI findings in three patients are shown, apparent diffusion coefficient (ADC) maps are calculated, and ADC measurements made from various regions of interest are documented. MRI showed diffuse swelling and areas of T2 high signal in supratentorial white matter, sparing the cortex and central gray matter structures. MRS findings indicated some degree of neuronal loss. DWI and ADC maps showed increased diffusion rates, suggesting a different type of tissue damage than that would be expected in vacuolating myelinopathies. We believe that DWI and ADC mapping would be of help in providing a baseline for monitoring the progression of the disease.     

Monoclonal antibodies to human platelet glycoprotein IIb beta that initiate distinct platelet responses

Hybridomas secreting monoclonal antibodies (MoAbs) to human platelet membrane glycoprotein IIb (GPIIb) were prepared by fusing cells of a mouse myeloma line to spleen cells from a BALB/c mouse immunized with purified GPIIb. Six of the hybridomas secreted MoAbs that recognized epitopes on the 23,000-dalton, disulfide-linked subunit of GPIIb, GPIIb beta. All six of these MoAbs agglutinated platelets in the absence of calcium. The agglutination titers of three of the MoAbs, however, were enhanced between 2 and 6 log2 dilutions when titrated in the presence of mmol/L of calcium. The enhancement in titer was the result of MoAb- induced platelet activation followed by platelet aggregation, a reaction that could also be initiated by the monovalent Fab fragments prepared from one of the MoAbs. The MoAbs did not significantly agglutinate platelets from patients with Glanzmann's thrombasthenia, confirming biochemical evidence that there is a paucity of GPIIb beta in the membranes of these cells. Our results show that MoAbs to epitopes on GPIIb beta initiate distinct platelet responses; therefore, they should be useful for studying the ways in which regions of surface glycoproteins are involved in platelet-platelet interactions. In addition, these reagents may prove of value in diagnosing and typing patients with Glanzmann's thrombasthenia.     

Successful intra-arterial thrombolytic therapy for a right middle cerebral artery stroke in a 2-year-old supported by a ventricular assist device

Embolic stroke is a common complication in patients on ventricular assist devices in both adults and children. The reported incidence of strokes in children supported by VAD's varies from 7 to 38%. The rapid increase in recent years in the availability of both adult and pediatric VADs will likely add to the overall prevalence of strokes in patients being bridged to heart transplant. Strokes in this population can be lethal as they frequently necessitate withdrawal of the extracorporeal device support and withdrawal from the organ transplant waiting list. We present a case of a fully anti-coagulated 29-month-old supported on a Berlin EXCOR LVAD (Berlin, Germany) with embolic stroke which was treated successfully with direct thrombolysis with recombinant tissue plasminogen activator. This is the first report which uses intra-arterial thrombolytics while on a ventricular assist device in a pediatric patient.     

Comparison of percutaneous nephrolithotomy and retrograde flexible nephrolithotripsy for the management of 2-4 cm stones: a matched-pair analysis

Study Type – Therapy (case control) Level of Evidence 3b What's known on the subject? and What does the study add? Recently European Association of Urology 2011 guidelines on urolithiasis recommended retrograde intrarenal surgery as the second‐line therapy for the treatment of kidney stones <10 mm in diameter. This study shows that retrograde intrarenal surgery may be an alternative therapy to percutaneous nephrolithotomy, with acceptable efficacy and low morbidity for 2–4 cm stones.

OBJECTIVE

• ? Currently, the indications for retrograde intrarenal surgery (RIRS) have been extended due to recent improvements in endoscopic technology. In this study, we compare the outcomes of percutaneous nephrolithotomy (PCNL) and RIRS in the treatment of 2–4 cm kidney stones.

MATERIALS AND METHODS

• ? Between September 2008 and January 2011, 34 patients who had renal stones ranging from 2 to 4 cm in diameter were treated with RIRS. The outcomes of these patients were compared with patients who underwent PCNL using matched‐pair analysis (1:1 scenario).
• ? The matching parameters were the size, number and location of the stones as well as age, gender, body mass index, solitary kidney, degree of hydronephrosis, presence of previous shock wave lithotripsy and open surgery.
• ? Data were analysed using Fisher's exact test, Student's t test and the Mann–Whitney U test.

RESULTS

• ? Stone‐free rates after one session were 73.5% and 91.2% for RIRS and PCNL respectively (P= 0.05). Stone‐free rate in the RIRS group improved to 88.2% after the second procedure.
• ? Mean operation duration was 58.2 (±) 13.4 min in the RIRS group but 38.7 (±) 11.6 min in the PCNL group (P < 0.0001). Blood transfusions were required in two patients in the PCNL group.
• ? Overall complication rates in the PCNL group were higher, but the differences were not statistically significant. Hospitalization time was significantly shorter in the RIRS group (30.0 + 37.4 vs 61.4 + 34.0 h, respectively; P < 0.001).

CONCLUSION

• ? Satisfactory outcomes can be achieved with multi‐session RIRS in the treatment of 2–4 cm renal stones. RIRS can be used as an alternative treatment to PCNL in selected cases with larger renal stones.

     

American College of Cardiology/American Heart Association preoperative assessment guidelines reduce resource utilization before aortic surgery

BACKGROUND: Methods used for evaluation of cardiac risk before noncardiac surgery vary widely. We evaluated the effect over time on practice and resource utilization of implementing the American College of Cardiology/American Heart Association Guidelines on Preoperative Risk Assessment. METHODS: We compared 102 historical control patients who underwent elective abdominal aortic surgery (from January 1993 to December 1994) with 94 consecutive patients after guideline implementation (from July 1995 to December 1996) and 104 patients in a late after guideline implementation (from July 1, 1997, to September 30, 1998). Resource use (testing, revascularization, and costs) and outcomes (perioperative death and myocardial infarction) were examined. Patients with and without clinical markers of risk for perioperative cardiac complications were compared. RESULTS: The use of preoperative stress testing (88% to 47%; P <.00001), cardiac catheterization (24% to 11%; P <.05), and coronary revascularization (25% to 2%; P <.00001) decreased between control and postguideline groups, respectively. These changes persisted in the late postguideline group. Mean preoperative evaluation costs also fell ($1087 versus $171; P <.0001). Outcomes of death (4% versus 3% versus 2%) and myocardial infarction (7% versus 3% versus 5%) were not significantly different between control, postguideline, and late postguideline groups, respectively. Stress test rates were similar for patients at low risk versus high risk in the historical control group (84% versus 91%; P =.29) but lower for patients at low risk after guideline implementation (31% versus 61%; P =.003). CONCLUSION: Implementation of the American College of Cardiology/American Heart Association cardiac risk assessment guidelines appropriately reduced resource use and costs in patients who underwent elective aortic surgery without affecting outcomes. This effect was sustained 2 years after guideline implementation.     

Allopurinol plus pentoxifilline in hepatic ischaemia/reperfusion injury

OBJECTIVES: Ischaemia/reperfusion injury of the liver is the major cause of liver dysfunction and cellular death in transplantation and in liver resection with hepatic pedicle clamping. Many agents are used to prevent this phenomenon, which occurs following interaction of different mediators during both ischaemia and reperfusion. In this study, we aimed to assess the effects of allopurinol, a xanthine oxidase inhibitor, and pentoxifilline, on liver ischaemia/reperfusion injury when used together and to compare these with the effects of using these agents singly. METHODS: Thirty-two rats were divided into four groups consisting of eight rats: Group C, control; Group P, pentoxifilline; Group A, allopurinol; and Group PA, pentoxifilline + allopurinol. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) levels were measured before hepatic pedicle clamping, on the 45th minute of ischaemia and 15 and 45 minutes after reperfusion. Group P rats were injected with 50 mg/kg pentoxifilline, Group A rats 50 mg/kg allopurinol and Group PA rats were injected with both agents 15 minutes before hepatic pedicle clamping. RESULTS: Ischaemia/reperfusion injury was produced by hepatic pedicle clamping, as demonstrated by AST, ALT and LDH increase. Injury prevention occurred in Groups P, A and PA. No significantly different (better) prevention was provided by giving allopurinol plus pentoxifilline to the rats. Furthermore, no difference was observed between the allopurinol and pentoxifilline injected groups in terms of preventing ischaemia/reperfusion injury. CONCLUSIONS: Pretreatment with allopurinol or pentoxifilline resulted in significantly lower hepatic enzyme elevation than that in controls in the rat liver ischaemia/reperfusion model. Using both agents does not provide better protection than using either agent alone.     

Delayed Diagnosis of Tuberculous Arthritis

Monoarticular tuberculosis （TB） affecting the knee is rare in all forms of TB （0.1-0.3%）. We present the case of a patient with tuberculous arthritis in whom the diagnosis was belated due to a lack of familiarity with the disease; here, we emphasize the difficulties associated with the diagnosing joint TB. A 20-year-old man was referred to our department due to swelling of the right knee and the presence of persistent, mild pain for 4 years. The lack of systemic evidence of this disease, the indolent course of disease, and the presence of non- specific symptoms renders early recognition of this disease difficult. Furthermore, in cases in which a diagnosis cannot be reached simply by culturing the synovial fluid, synovial biopsy cultures should be considered m the diagnostic process, due to the high rate of positivity of such cultures. The diagnosis and treatment of articular TB are both urgent matters; surgical debridement and strict adherence to antituberculous chemotherapy tend to yield a satisfactory functional outcome.     

Autosomal dominant periodic fever with AA amyloidosis: tumor necrosis factor receptor-associated periodic syndrome (TRAPS) in a Turkish family

We investigated the presence of tumor necrosis factor receptor-associated periodic syndrome (TRAPS) in a Turkish family with recurrent fever and systemic reactive (AA) amyloidosis. A missense mutation in exon 3 of the TNFRSF1A gene, resulting in an amino acid substitution Phe60Leu (F60L) was found in the proband and his father. These are the first confirmed TRAPS cases in the Turkish population. This family highlights the importance of onsidering all the causes of inherited fevers and performing thorough clinical and genetic investigations to secure a diagnosis, even in populations in which familial Mediterranean fever (FMF) is highly prevalent.     

Glutathione peroxidase 1 (GPX1) genetic polymorphism, erythrocyte GPX activity, and prostate cancer risk

Glutathione peroxidase 1 (GPX1) is a ubiquitously expressed selenium-dependent enzyme that protects cells against oxidative damage by reducing hydrogen peroxide and a wide range of organic peroxides. Some epidemiological studies have correlated low GPX activity or particular GPX1 polymorphisms with enhanced risk of cancer, although these correlations have not been consistently observed in all populations. Therefore, we conducted the present study to evaluate the possible association of GPX1 Pro198Leu polymorphism and erythrocyte GPX activity with the risk of developing prostate cancer and to clarify whether erythrocyte GPX activity levels were correlated with the GPX1 Pro198Leu genotype in the Macedonian population. The GPX1 Pro198Leu genotype was determined in 82 prostate cancer cases and 123 control individuals. We found an overall protective effect of the variant Leu allele of the GPX1 polymorphism on the prostate cancer risk. Heterozygous carriers of the variant Leu allele had a significantly lower risk of prostate cancer compared with homozygous wild-type individuals (OR, 0.38; 95% CI, 0.20–0.75; P = 0.004). Erythrocyte GPX activity was analyzed in 73 cases and 91 controls. The erythrocyte GPX activity in the cancer group was lower than in the healthy controls. Additionally, we compared the erythrocyte GPX activity in the control group of 90 subjects and found no significant differences by genotype. These findings suggest that individual susceptibility of prostate cancer may be modulated by GPX1 polymorphism and that the combination of genetic factors involved in oxidative response with environmental carcinogens may play an important role in prostate carcinogenesis.