Can serums be replaced by Mueller-Hinton agar in germ tube test?

BACKGROUND: The germ tube test (GTT) is inexpensive, easy, and well-defined test that differentiates Candida albicans (excluding Candida dubliniensis and Candida africana) from other species. The aim of this study was to evaluate various serums (i.e., human, rabbit, horse, and fetal bovine serum) used in the GTT and Mueller-Hinton agar (MHA). MATERIALS AND METHODS: Fifty species isolated from various clinical samples that were defined as C. albicans by both conventional and DNA sequence analysis methods were included in the study. One to two colonies of C. albicans were mixed into 0.5-1 ml of fetal bovine serum, horse serum, rabbit serum, and human serum. Serums and MHA were incubated at 37°C for GTT. They were removed from the incubator and evaluated after 30 min, 1 h, 2 h, and 3 h of incubation. The GTT was accepted to be positive only if germ tube was 1/2 the width and 3 times the length of the parent yeast cell and with no constriction at the point of origin. RESULTS: When the use of serums and MHA for GTT was statistically evaluated, according to the positive scoring, the best results were obtained with MHA and with rabbit, horse, and fetal bovine serum, respectively. The best definition over time statistically was the third hour. CONCLUSION: It is suggested that inexpensive MHA is a fast, appropriate, and reliable medium for the probable diagnosis of GTT and C. albicans; however, additional studies are still needed to define other Candida species.

Investigation of possible virulence factors in Candida strains isolated from blood cultures.

BACKGROUND: The Candida species, which are one of the most common causes of nosocomial bloodstream infections, present with high mortality and morbidity rates. This study aims to investigate the production of esterase, phospholipase, proteinase, and biofilm formation ability of the Candida strains isolated from the blood cultures. MATERIALS AND METHODS: Between June 2011 and July 2012, the Candida strains, which were isolated from blood cultures of a total of 50 patients, were studied. The esterase activity was analyzed in the Tween-80 agar, while phospholipase activity was studied in the egg yolk agar. The proteinase activity and biofilm formation were identified by using the petri dish method and microplate method, respectively. RESULTS: Of 50 specimens obtained from individual patients, 17 (34%) were identified as C. albicans, 14 (28%) as C. glabrata, 9 (18%) as C. parapsilosis, 5 (10%) as C. krusei, 4 (8%) as C. kefyr, and 1 (2%) as C. tropicalis. The rate of proteinase, phospholipase, and esterase positivity was higher in the C. albicans isolates. Biofilm formation was the highest in the C. parapsilosis strains. CONCLUSIONS: Higher rate of virulence factors in the most commonly isolated Candida species than other species indicates that these virulence factors play a crucial role in the pathogenesis.

Iodine status and goiter prevalence in Turkey before mandatory iodization.

Endemic goiter is an important public health problem in Turkey. Legislation for mandatory iodization of household salt was passed in July 1999. Current study is aimed at ascertaining the goiter prevalence and iodine nutrition in school-age children (SAC) living in known endemic areas of Turkey. Sonographic thyroid volumes (STV) and urinary iodine concentrations (UIC) of 5,948 SAC from 20 cities were measured between 1997-1999. STV of 31.8% of the SAC examined stayed above the upper-normal limits for the same age and gender recommended by the World Health Organization (WHO). Goiter prevalence ranged between 5 to 56% and median UIC ranged between 14 to 78 microg/l, indicating severe to moderate iodine deficiency (ID) in 14 and mild ID in 6 of the cities surveyed. Neither of the cities was found to have sufficient median UIC levels. The current study shows that endemic goiter is an important public health problem and iodine nutrition is inadequate nationwide. It also provides reliable scientific evidence and shows the need for a controlled and effective iodine supplementation program nationwide. Mandatory iodization of household salt seems to be the essential measure taken for the moment, additional measures may be needed in the near future.

Endemic goiter, thiocyanate overload, and selenium status in school-age children.

Iodine deficiency (ID) and related disorders are still major, yet unresolved health concerns. Recently, in a systematic survey of school-age children (SAC), we reported severe to moderate ID, in Ankara and three cities from Black Sea region of Turkey. The current study attempted to evaluate selenium (Se) status, thiocyanate (SCN-) overload, and their possible contribution to the goiter endemics and thyroid hormone profile observed in these cities. Thyroid ultrasonography was performed and serum Se, SCN(-), thyroid hormones, sensitive TSH (sTSH) levels, and, urinary iodine concentrations (UICs) were determined from 251 SAC (9-11 yr old). Thyroid volumes (TVs) exceeding recommended upper normal limits and median UIC indicated goitre endemics and moderate to severe ID in the areas studied. Mean serum SCN(-) concentrations were found to be greater than the controls from the literature. The UIC/SCN(-) ratio was found to be lowest in Bayburt and Trabzon denoting that SCN(-) overload may contribute to the goiter endemics. Serum Se concentrations represent a marginal deficiency in the four areas studied. No significant correlations between serum Se concentrations and the other parameters studied (i.e., TV, SCN(-), thyroid hormones, sTSH, UIC) was detected. In conclusion, this study showed that selenium is also marginally deficient in the iodine-deficient endemic areas studied, but this has little or no impact on the thyroid hormone profile and the goiter endemics. SCN(-) overload may contribute to the endemics, especially for the areas where iodine is severely deficient. An effective iodine supplementation program will not only resolve the goiter endemics but also the consequence of SCN(-) overload as well in the endemic goiter areas studied.

Iodine status and thyroid volumes of school age children from Northern Cyprus.

In an epidemiological study carried out in eight different inland and coastal areas from northern part of Cyprus Island 625 School Age Children (SAC) aged 9 and 10 years, underwent thyroid ultrasonography for determination of thyroid volume (TV). Urinary iodine concentration (UIC) was measured from morning urine samples taken from all of the children. Mean TV was 3.2+/-1.0 ml, 3.3+/-0.8 ml and 3.8+/-1.1 ml, 3.7+/-1.1 ml for 9- and 10-year-old girls and boys respectively. None of the SAC had TV exceeding recommended upper limits for their age and gender. Median UIC of the whole group was 120 microg/l (11-900 microg/l) and only 12.6% of the SAC had UIC below 50 microg/l indicating adequate iodine intake. In this first epidemiological survey conducted in the northern part of the Cyprus Island, iodine status was found to be satisfactory and goiter does not pose a public health problem at the time of the study. Periodical surveys are required especially for the regions which have marginally adequate values and for a coastal region with a significantly higher median value of UIC compared to the others (ie 458 microg/l) (p<0.001).

Moderate to severe iodine deficiency in three endemic goitre areas from the Black Sea region and the capital of Turkey.

Endemic goitre is still an important and underestimated health concern in Turkey. The overall prevalence had been calculated as 30.3% by palpation in a national survey conducted in 1995. However, direct evidence that iodine deficiency (ID) is the major cause of the endemic were lacking until now. We measured sonographic thyroid volumes (STV), urinary iodine concentrations (UIC) in 1226 school age children (SAC) (9-11 year old) from Ankara the capital of Turkey located in the central Anatolia, and three highly endemic goitre areas of the Black Sea region. A considerable number of school age children (SAC) were found to have STV exceeding the recommended upper normal limits for their age and gender obtained from iodine-replete European children (i.e. 26.7, 40.3, 44.8 and 51.7% of children from Ankara, Kastamonu, Bayburt and Trabzon respectively). UIC indicated moderate to severe ID in these areas with median concentrations of 25.5, 30.5, 16.0 and 14 microg/L respectively. This study showed severe to moderate ID as the primary etiological factor for the goitre endemic observed in Ankara and the Black Sea region of Turkey.

Effect of octreotide treatment on Graves' ophthalmopathy.

In this study, nine patients with Graves' ophthalmopathy with positive clinical activity score (CAS), who were either unresponsive or not suitable for glucocorticoid treatment, were given 100 microg of octreotide three times daily, subcutaneously, for three months. The mean age was 49+/-13 years. All patients were under either propylthiouracil or methimazole therapy and were euthyroid for at least one month prior to the start of the octreotide treatment. The mean degree of proptosis as measured with the Hertel exophthalmometer decreased slightly after the treatment (22.0+/-3.0 vs 19.6+/-2.4 for the right eye and 22.2+/-1.9 vs 20.2+/-2.2 for the left eye; p<0.05). The mean activity score decreased from 3.2+/-0.8 to 1.7+/-1.1 (p<0.005) and the mean score of eye signs according to the NOSPECS classification showed improvement with octreotide therapy (3.2+/-0.7 vs. 2.2+/-1.4; p<0.05). Seven patients responded favorably to octreotide treatment. In the remaining two no improvement was observed. Four of the responders could be followed up for 20 months after the treatment and all maintained the favorable state of eye findings obtained with octreotide. We conclude that octreotide seems to be a safe and effective drug in Graves' ophthalmopathy, especially in improving soft tissue involvement, and can be used in patients who are unresponsive to glucocorticoid treatment or who cannot use these drugs for some reason.