Molecular epidemiology of penicillin-resistant Streptococcus pneumoniae in a university hospital, Ankara, Turkey

Penicillin-resistant Streptococcus pneumoniae isolates (n = 76) from clinical samples of patients admitted to Hacettepe University Hospital between January 1997 and December 2001 were included in the study. MICs of penicillin G, erythromycin A, clindamycin, cefaclor, cefotaxime, vancomycin, chloramphenicol, tetracycline, ciprofloxacin and rifampicin were determined by agar dilution. The isolates were serogrouped on the basis of the Neufeld Quellung reaction and were typed by BOX-PCR. Genetic polymorphism of the penicillin resistance genes pbp2b and pbp2x was investigated by restriction fragment length polymorphism (RFLP) analysis. Of the 76 isolates tested, 64 (84.2%) showed intermediate resistance to penicillin, while 12 (15.8%) were resistant to higher levels of penicillin (MIC > or = 2 mg/L). The resistance patterns of the isolates revealed six different resistance profiles. There were 22 different serotypes, with c. 55% of the isolates belonging to serotypes 23B, 19A, 19F, 14, 6 A and 9V. Five distinct patterns for pbp2b and 12 distinct patterns for pbp2x were obtained by RFLP analysis of penicillin-binding protein genes. The combination of these patterns allowed isolates to be classified into 22 fingerprint subgroups. BOX-PCR analysis showed that the isolates fell into 14 distinct BOX genotypes, with 33 subtypes. Serotype 9V isolates with pbp genotype 2-6 and BOX-PCR type 4, 4.1 or 4.2 were related to the pandemic clone Spain(9V)-3. No relatedness to other international clones was detected among the other study strains, but genetic relatedness was observed among some of the serotype 19A and 23B isolates. Overall, the results demonstrated that most of the penicillin-resistant pneumococcal isolates in Turkey, other than those belonging to serotypes 9V, 19A and 23B, were derived from several independent clones, possibly resulting from multiple importation of strains originating from outside the country. Differences in pbp patterns, serotypes and resistance profiles among isolates that showed similar BOX-PCR patterns supported the hypothesis that horizontal transfer of capsular genes, pbp genes and other genetic determinants between S. pneumoniae and viridans group streptococci may have occurred.     

Haematologic consequences of viral infections including serum iron status

Twenty-seven children with mumps or chickenpox were taken as a model to evaluate the haematological consequences of viral infections including serum iron status. Blood samples were obtained from all patients at presentation and on the 21 st day of the disease. While haemoglobin, haematocrit, and meam corpuscular volume levels were similar in two measurements (P>0.05), the mean leucocyte, absolute lymphocyte and thrombocyte counts, mean serum iron, serum iron binding capacity and transferrin saturation levels were lower at presentation than on the 21 st day of the disease. The serum iron levels were below 30 g/dl in 16 (59.2%) patients at presentation while only 4 (14.8%) had low values on 21 st day. Twenty-four (88.9%) patients had an increment in the serum iron binding capacity levels and 2 (7.6%) reached values above the normal range on the 21 st day. Int 21 (77.8%) patients, the transferrin saturation levels were below the expected ranges at presentation but 26 (96.3%) showed an increment on the 21 st day. However, the mean ferritin level was higher at presentation. Therefore, during the evaluation of patients for anaemia, the presence of a recent acute viral infection should be documented so as to avoid unnecessary iron medication.     

The place of diuretic enhanced Doppler sonography in distinguishing between obstructive and non-obstructive hydronephrosis in children

OBJECTIVE: In an attempt to differentiate obstructive from non-obstructive dilation of the renal collecting system in children, a prospective clinical study was carried out. MATERIAL AND METHODS: During duplex Doppler sonography examination in 23 children resistive index (RI) and pulsatility index (PI) and RI ratio values before and after intraverous furasemide administration were compared with the findings obtained with diuretic renogram examination (t(1/2)). RESULTS: Evaluation of the results demonstrated that diuresis RI and PI determination may aid differentiation of severely obstructed renal units from those with slight (equivocal) or no obstruction. CONCLUSION: Kidneys with severe UPJ obstruction tended to have more elevated RI and PI values than the non-obstructed or equivocally obstructed ones. Again, determination of RIR values for each kidney showed the same elevation in severely obstructed kidneys, while non-obstructive or indeterminately obstructed ones demonstrated statistically insignificant changes.     

Relation between radionuclide imaging and pathologic findings of ureteropelvic junction obstruction in neonatal hydronephrosis

OBJECTIVE: An excessive amount of collagen fibers around the muscle cells in the ureteropelvic junction could be responsible for obstruction in patients with hydronephrosis. We aimed to elucidate the ultrastructure of the ureters and correlate this finding with the prognostic outcome and to correlate the histopathological findings with diuretic radionuclide renography findings. MATERIAL AND METHODS: Biopsy specimens of 20 children who underwent dismembered pyeloplasty for ureteropelvic junction obstruction were analyzed. The patients were grouped according to their age: infants (<12 months) and others (>12 months). Diuretic radionuclide imaging was performed using (99m)Tc mercaptylacetyltriglycine in the pre- and postoperative periods. Changes in differential renal function and excretion patterns on diuretic renography were evaluated in relation to the findings noted on histopathological examination of the biopsy specimens. Excretion patterns were classified as follows: A, normal; B, responsive to diuretic; C, minimal response to diuretic with some excretion after postural change; and D, very poor/no drainage despite diuretics. Biopsy materials were analyzed for the presence and extent of inflammation, fibrosis and changes in the smooth muscle layer using Masson's trichrome stain and immunohistochemical staining. Histopathological findings were graded from zero to three, depending on severity. RESULTS: In patients aged <12 months, preoperative differential renal function (DRF) was associated with fibrosis (F) and smooth muscle hypertrophy (SMH) [mean (SD) DRF for both F and SMH were Grade 0-1, 47.8% (6.4%); Grade 2-3, 36.2% (11.3%); p<0.05]; and change in DRF was associated with inflammation [Grade 0-1, -0.1% (4.0%); Grade 2-3, 5.8% (3.0%); p<0.05]. Excretion patterns or improvement in excretion were not associated with any of the histopathological features. Change in DRF was significantly associated with inflammation Grade 2-3 (beta coefficient, 5.8; 95% CI 1.4-10.3). CONCLUSIONS: Histopathological evaluation of renal parenchymal biopsy specimens obtained during pyeloplasty may be useful to provide an objective method for predicting the recovery of renal function. In addition, this will allow comparison of the types of histopathological alterations with the changes in differential renal function in order to predict the potential final improvement.     

Eculizumab therapy in a patient with dense-deposit disease associated with partial lipodystropy

Background

Dense deposit disease (DDD) (also known as membranoproliferative glomerulonephritis type II) in childhood is a rare glomerulonephritis with frequent progression to end-stage renal disease (ESRD) and a high recurrence after kidney transplantation. The pathophysiologic basis of DDD is associated with the uncontrolled systemic activation of the alternative pathway (AP) of the complement cascade.

Case-diagnosis/treatment

A 14-year-old girl presented with edema and nephrotic range proteinuria. Blood tests showed hypoalbuminemia, nephrotic range proteinuria, normal renal function, and a low C3 level. Renal biopsy confirmed the diagnosis of crescentic DDD. Complement analysis revealed strong AP activation (low C3), positive C3 nephritic factor (C3NeF), and a decreased complement factor H (CFH) levels with CFH polymorphisms. Therapy with eculizumab was considered after the failure of corticosteroid and plasmapheresis to modulate the ongoing massive proteinuria and persistence of low serum C3 levels. There was a marked clinical and biochemical response following the administration of eculizumab.

Conclusions

Our case emphasizes the efficacy of eculizumab in the management of crescentic DDD in a patient with a normal renal function, in a short follow-up period. Considering previously reported cases, it appears that eculizumab represents a promising new approach which may prevent progression to ESRD in a subset of patients with DDD.     

Gamma probe localization of cranial bone lesions: technical note

BACKGROUND: Intraoperative localization of cranial bone lesions may be challenging especially when the lesion is not well demonstrated on computed tomography (CT) scan but solely on a radio-isotope bone scan. We hereby demonstrate a technique for localizing such lesions using an intraoperative gamma probe reader and summarize the relevant literature. METHODS: A case report of a temporal osteoid osteoma causing local pain and unresponsive to conservative treatment is presented. The lesion was demonstrated preoperatively solely on a bone scan, and was intra-operatively localized by a gamma probe reader. RESULTS: The lesion was totally excised with normal background readings after lesion removal. Six months after total removal of the osteoid osteoma, the patient is asymptomatic. CONCLUSION: Intraoperative gamma probe reader is a simple, effective, and safe method for intra-operative localization of bone lesions, which are positive on bone scans. It is especially useful for skull lesions that are not demonstrated by other imaging methods.