A schwannoma mimicing hypopharyngeal carcinoma

Hypopharyngeal schwannoma is quite rare, with only nine cases presented in the literature to our knowledge. The presentation itself requires a distinction from malignant hypopharyngeal disease, which is usually the initial diagnosis. A transcervical approach and laryngomicrosurgery are two possible operating methods for the treatment of hypopharyngeal schwannoma. The selection of the surgical method depends on the size of the tumor. For this case, we preferred the transcervical approach without tracheotomy. In contrast to previous case reports, we were unable to trace the original nerve.     

The use of chloride–sodium ratio in the evaluation of metabolic acidosis in critically ill neonates

Acid-base disturbances have been usually evaluated with the traditional Henderson-Hasselbach method and Stewart's physiochemical approach by quantifying anions of tissue acids (TA). It is hypothesized that an increase in tissue acids during metabolic acidosis would cause a compensatory decrease in the plasma chloride (Cl) relative to sodium (Cl-Na ratio) in order to preserve electroneutral balance. Therefore, we aimed to investigate the use of Cl-Na ratio as a bedside tool to evaluate the identifying raised TA in neonates as an alternative to complex calculations of Stewart's physiochemical approach. This retrospective study was conducted between January 2008 and December 2009. Infants were included in the study when blood gas analysis reveals a metabolic acidosis; pH?<7.25 and sHCO(3) concentration was <22?mEq/L. The Cl-Na ratio, sodium-chloride difference (Diff(NaCl)), anion gap (AG), albumin-corrected AG (AG(corr)), strong ion difference (SID), unmeasured anions (UMA), and TA were calculated at each episode of metabolic acidosis. A total of 105 metabolic acidosis episodes occurred in 59 infants during follow-up. Hypochloremic metabolic acidosis occurred in 17 (16%) of samples, and all had increased TA. The dominant component of TA was UMA rather than lactate. There was a negative correlation between the Cl-Na ratio and SID, AG(corr), UMA, and TA. Also, there was a positive correlation between Diff(NaCl) and SID, AG(corr), UMA, and TA. Base deficit and actual bicarbonate performed poorly in identifying the TA. In conclusion, our study suggested that Diff(NaCl) and Cl-Na ratio are simple and fast, and may be an alternative method to complex Stewart's physiochemical approach in identifying raised UMA and TA in critically ill neonates.     

Regulation of the tonsil cytokine milieu favors HIV susceptibility

Mucosal associated lymphoid tissues are major targets of HIV during early infection and disease progression but can also provide a viral safe haven during highly active antiretroviral therapy. Among these tissues, the tonsils remain enigmatic regarding their status as primary and/or secondary sites of retroviral infection. To dissect the mechanisms underlying susceptibility to HIV in this compartment, isolated tonsil cells were studied for phenotypic and functional characteristics, which may account for their permissiveness to infection. For this, tonsil cells and PBMC were infected in parallel with HIV, and viral replication was monitored by p24 ELISA. Our results demonstrate that unstimulated tonsil cells were more readily infected than PBMC with HIV. Phenotypic characterization of the tonsil cells revealed heterogeneous lymphoid populations but with increased expression of early activation markers and the viral co-receptor CXCR4, relative to PBMC, all of which may contribute to viral susceptibility. Furthermore, the cytokine microenvironment appeared to be key in facilitating HIV infection and tonsil-secreted products enhanced HIV infection in PBMC. Of the cytokines detected in the tonsil supernatants, TH2 cytokines, particularly IL-4, promoted HIV infection and replication. Interestingly, this TH2 profile appeared to dominate, even in the presence of the TH1 cytokine IFNgamma and the anti-viral factor IFNalpha, likely due to the enhanced expression of suppressor of cytokine signaling (SOCS) proteins, which may disengage IFN signaling. These and other local environmental factors may render tonsil cells increasingly susceptible to HIV infection.     

Antibiotic susceptibilities of enterococci isolated from Turkish children

To evaluate the antibiotic resistance rates of enterococci isolated at Hacettepe Children's Hospital, in vitro antibiotic susceptibility tests were performed in 77 enterococci (32 hospital, 45 nonhospital strains) isolated from various clinical specimens in 1994. Microbroth dilution tests against ampicillin, vancomycin, gentamicin and streptomycin were performed according to the NCCLS standards. High-level resistance to aminoglycosides was investigated. Ampicillin resistance rates were 21.9 percent and 2.2 percent for hospital and nonhospital strains, respectively (p < 0.01). The same rates were 46.9 and 13.3 percent for gentamicin (p < 0.01), and 15.6 and 13.3 percent for streptomycin (p = 0.25). No resistance was detected against vancomycin. Six strains (7.8%) showed high-level resistance to both aminoglycosides studied. Special attention should be paid to enterococci isolated from hospitalized patients. Appropriate antibiotic use in serious infections can only be achieved by choosing an appropriate regimen according to antibiotic susceptibility tests. Periodic evaluation of the antibiotic susceptibility patterns of enterococci is necessary for the empirical treatment of infections due to these microorganisms.     

Nephrocalcinosis in glucose-galactose malabsorption: nephrocalcinosis and proximal tubular dysfunction in a young infant with a novel mutation of SGLT1

We report an association of proximal renal tubular dysfunction in a 50-day-old girl with glucose-galactose malabsorption who was found to have nephrocalcinosis, but no sign of nephrolithiasis. A novel homozygous nonsense mutation at 267Arg →stop (CGA→TGA) in the Na⁺-dependent glucose transporter (SGLT1) was found in loop 5 connecting transmembrane segments 6 and 7, indicating the complete loss of glucose transport activity. This case indicates that hypercalcaemia, nephrocalcinosis and proximal tubular dysfunction may be seen in association with glucose-galactose malabsorption and that most of these abnormalities improve with a glucose-galactose-free diet.     

Is elective neck dissection necessary for the surgical management of T2N0 glottic carcinoma?

Objective

Evaluation of neck metastasis incidence in surgically treated T2N0M0 glottic carcinoma patients and discussion the necessity of elective neck dissection in this subset of larynx carcinomas.

Materials and methods

The patients who were staged clinically and radiologically as T2N0M0 glottic carcinoma having surgical intervention for their primary tumor and elective neck dissection between March 1996 and July 2009 with at least 2 years of follow up were included in the study. The recordings of patients were evaluated retrospectively for primary tumor location, vocal cord mobility, type of laryngectomy and neck dissection, results of histopathological examination, number of dissected lymph nodes for each specimen and for local and regional failure during the follow up.

Results

In the 13-year study period, 24 consecutive patients with a mean age of 56.4 were treated surgically with 20 frontolateral, three vertical laryngectomies and one cricohyoido-epiglottopexy; 19 lateral and 5 functional neck dissections were performed for the necks. Histopathological examinations of the neck dissection specimens revealed an average of 32 lymph nodes (8–65) and there was no metastasis in any of these specimens. After an average 58 months of follow-up, only one patient had local failure and no patients had regional failure.

Conclusion

As occult metastasis was not detected in any of the neck dissection specimens in cT2N0M0 patients and no regional failure was experienced during the follow-up period, it was concluded that the neck could be followed up without performing elective neck dissection in the surgical management of cT2N0M0 glottic carcinoma patients.