Etiological diagnosis of bloodstream infections through a multiplex real-time polymerase chain reaction test in pediatric patients: a case series from a tertiary Italian hospital

BACKGROUND

The outcome of bloodstream infections (BSIs) is strongly related to microbiological diagnosis. Several factors may reduce blood culture (BC) diagnostic yield in pediatric BSIs, making the application of molecular methods quite promising.

METHODS

Multiplex real-time polymerase chain reaction (PCR) tests (the LightCycler Septifast Test MGRADE by Roche Diagnostics--LC-SF) performed in the tertiary centre of Regina Margherita Children's Hospital (Turin, Italy) over a 3-year period were retrospectively evaluated. Results of the LC-SF test were compared with those of BC (Automated Bact/Alert 3D, Biomerieux) collected at a close time point.

RESULTS

545 LC-SF tests were collected from 289 patients (183 males, median age 6.8 years, interquartile range (IQR) = 2.7-13.1); 163 had congenital or acquired immunodeficiency. In 515 cases (94.5%) the LC-SF test was performed with ongoing empirical antimicrobial therapy. Etiological definition was achieved in 111 BSI cases (20.4%). Both LC-SF and BC identified the responsible pathogen in 39 episodes. The LC-SF test alone gave a positive result in 29 septic episodes; BC alone permitted the etiological diagnosis in 43 episodes, but isolates were not included in the LC-SF master list in 10 cases. A 26% increase in bacterial identification chances due to the LC-SF test was documented. Cohen's kappa test indicated a moderate strength of agreement (0.49) between LC-SF tests and BCs closely collected.

CONCLUSIONS

BC remains the gold standard for the etiological diagnosis of BSIs, but PCR methods proved to be a valuable adjunctive diagnostic tool in pediatric BSIs, especially in children receiving empirical chemotherapy.

Natural history of vertically acquired HCV infection and associated autoimmune phenomena

The natural history of vertically acquired HCV infection is ill defined. The aim of this study was to outline the natural course of vertical HCV infection in a cohort of untreated children, including rate of spontaneous viral clearance, frequency and features of HCV-related autoimmune disorders. Children with vertical HCV infection were prospectively followed from the first month of life with regular clinical and laboratory assessments. Statistical analysis was performed using Prism 5.0. Forty-five children (median age 12 years, interquartile range 6.9-15.5) were studied. Genotype 1 was predominant (53.3 %). Spontaneous viral clearance was achieved by 12 patients (26.7 %) and associated with genotype 3. Alanine-amino-transferase levels were increased in most children in the first 2 years of life with higher values in those who later cleared the infection. All children were asymptomatic for liver disease. Transient elastography (32 patients) showed mild or moderate fibrosis in nine and two cases, respectively. Non-organ-specific autoantibodies were detected in 24 children (53.3 %) independently of viremia; of these, one developed type-1 diabetes. Cryoglobulinemia was associated with genotype 1 infection and found in 15 subjects (33.3 %): two had low C4 levels and persistent proteinuria.

CONCLUSIONS

Vertically acquired HCV infection may result in spontaneous clearance in up to 27 % of children. Resolution of infection is higher with genotype 3, usually occurs in preschool age and persists over time. Chronic infection is generally asymptomatic, although hepatomegaly and mild fibrosis may develop. Autoantibodies and cryoglobulins are frequent, whereas the associated clinical manifestations are rare.

Factors useful in predicting the success of oocyte donation: a 3-year retrospective analysis

OBJECTIVE

To establish prognostic relevance of parameters assessed in oocyte donation cycles.

DESIGN

Retrospective analysis.

SETTING

Large university-based donor oocyte program.

PATIENT(S)

All oocyte recipient cycles achieving embryo transfer from September 1995 to October 1998.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Pregnancy.

RESULT(S)

Recipient age and reproductive status, day 9 and 12 serum estradiol (E(2)) levels and a progesterone (P) level obtained 2 days after initiation of hormonal therapy did not correlate with pregnancy. Endometrial thickness, but not endometrial pattern, was useful in predicting pregnancy outcome. The clinical pregnancy and live-birth rate in cycles where the endometrial thickness was less than 8 mm was significantly lower when compared to cycles with an endometrial thickness > or =9 mm. Cycles where optimal quality embryos were transferred had the highest implantation (36%), clinical pregnancy (63%) and live birth (54%) rates and these rates were significantly higher than those of cycles where only poor quality embryos were available for transfer (10% implantation, 17% clinical pregnancy, and 8% live birth rates, respectively; P<.05).

CONCLUSION(S)

The most reliable predictive factors for pregnancy in oocyte donation cycles are the quality of the embryos transferred and the recipient's mid-cycle endometrial thickness. Recipient monitoring should minimally include ultrasound assessment of endometrial thickness.

A two- versus three-embryo transfer: the oocyte donation model

OBJECTIVE

To compare implantation and pregnancy rates in oocyte recipients undergoing a two-embryo versus three-embryo transfer, 3 days after retrieval.

DESIGN

Retrospective comparative analysis.

SETTING

University-based in vitro fertilization center.

PATIENT(S)

All oocyte recipients undergoing embryo transfer from January 1, 1997 through August 31, 1999.

INTERVENTION(S)

Recipients received two or three embryos.

MAIN OUTCOME MEASURE(S)

Implantation, and clinical and multiple pregnancy rates.

RESULT(S)

Seventy-three recipients underwent a two-embryo transfer, and 376 had three embryos replaced. The numbers of oocytes retrieved (12.7 +/- 0.89 vs. 13.1 +/- 0.36) and embryos obtained (8.05 +/- 0.65 vs. 8.77 +/- 0.27) did not differ between the two-embryo and three-embryo transfer groups, nor did the proportion of patients with embryo cryopreservation (54.3% vs. 42.6%, respectively). There was no significant difference in pregnancy or implantation rates when comparing those patients with a two-embryo transfer to those with a three-embryo transfer. Significantly, 13.8% of the pregnancies in the three-embryo transfer group were triplet.

CONCLUSION(S)

Reducing the number of embryos transferred in an oocyte donation cycle can lower the incidence of triplet pregnancies without significantly lowering the overall pregnancy rate.

In vitro fertilization outcome relative to embryo transfer difficulty: a novel approach to the forbidding cervix

OBJECTIVE

To assess the impact of ET difficulty on IVF outcome and to optimize the ET procedure.

DESIGN

Retrospective analysis of IVF outcome by ET catheter type and ET difficulty. Prospective treatment and follow-up of patients with a history of extremely difficult cervical passage.

SETTING

Large university-based IVF program.

PATIENT(S)

All patients < 40 years of age undergoing IVF-ET from September 1995 to May 1998.

INTERVENTION(S)

Surgical correction of cervical stenosis.

MAIN OUTCOME MEASURE(S)

Pregnancy and embryo implantation rates.

RESULT(S)

Only 0.6% of ETs were "extremely difficult." Pregnancy rates were not statistically significantly different among ETs graded easy, moderate, and difficult. In contrast, no pregnancies occurred in the rare "extremely difficult" ET group. Eight patients with a history of extremely difficult cervical passage underwent surgical correction of their cervical stenosis. Twelve postoperative IVF-ET in these women resulted in eight clinical pregnancies, six of which were multiple gestations. The embryo implantation rate of these cycles was 42.2%.

CONCLUSION(S)

Patients with a history of extremely difficult ET may benefit from hysteroscopic evaluation and possible modification of their cervical canal before a future IVF attempt.

Fertility after hysteroscopic resection of submucous myomas

STUDY OBJECTIVE

To analyze fertility outcomes after resection of submucous myomas by operative hysteroscopy in infertile women.

DESIGN

Retrospective analysis (Canadian Task Force classification II-2).

SETTING

Academic tertiary referral center.

PATIENTS

Forty-one women (age 28-42 yrs) old with primary and secondary infertility, and histologically proved submucous myomas. Intervention. Hysteroscopic myomectomy performed with a rigid resectoscope.

MEASUREMENTS AND MAIN RESULTS

Of the 41 patients, 25 (60.9%) became pregnant overall and 20 (48.7%) delivered at term. Seventeen patients delivered a single fetus. Five delivered twins, three at term and two at 33 and 35 weeks. One woman delivered triplets at 31 weeks. The total delivery rate was 56.0%. Two women miscarried, at 6 and 8 weeks. One patient developed postoperative Asherman's syndrome.

CONCLUSION

Our results indicate that hysteroscopic myomectomy improves fertility in previously infertile women. Resection is a viable alternative to abdominal myomectomy for submucous myomas. (J Am Assoc Gynecol Laparosc 6(2):155-158, 1999)

Enhancement or initiation of testicular sperm motility by in vitro culture of testicular tissue

OBJECTIVE

To describe different techniques of testicular tissue culture and their effect on sperm motility, mainly in cases of totally immotile spermatozoa, and to compare the effect of in vitro culture with that of motility stimulants.

DESIGN

Prospective study.

SETTING

University teaching hospital.

PATIENT(S)

Ten patients undergoing testicular biopsy for diagnostic purposes or for intracytoplasmic sperm injection.

INTERVENTION(S)

Dissected testicular biopsy samples and tissue blocks were cultured at 37 degrees C for up to 96 hours. Immediately after dissection, immotile testicular spermatozoa were incubated for 30 minutes in pentoxifylline and 2-deoxyadenosine.

MAIN OUTCOME MEASURE(S)

Sperm motility and vitality.

RESULT(S)

Overall, dissected samples showed improved sperm motility, which peaked within 48 hours of culture. Unlike motility, vitality declined linearly, from 56.3%+/-19% at initial assessment to 18.8%+/-11% at 96 hours. Five samples had initially immotile spermatozoa, of which four acquired motility at 48 hours. In vitro culture showed results comparable with those of incubation with pentoxifylline and 2-deoxyadenosine. Culture of tissue blocks did not improve motility or vitality compared with dissected tissue.

CONCLUSION(S)

The motility of testicular spermatozoa was enhanced or initiated after in vitro culture. Testicular biopsy culture may be an alternative to the use of motility stimulants to obtain motile spermatozoa for intracytoplasmic sperm injection, particularly when oocytes are not immediately available.

Genetic screening of prospective oocyte donors

OBJECTIVE

To report our experience with genetic screening of oocyte donor candidates and to determine the frequency with which significant genetic issues are identified.

DESIGN

Prospective genetic screening of oocyte donor candidates.

SETTING

University hospital oocyte donation program.

PATIENT(S)

Women presenting consecutively as volunteer oocyte donors.

INTERVENTION(S)

Genetic screening was performed by pedigree analysis and laboratory studies.

MAIN OUTCOME MEASURE(S)

Inclusion in the oocyte donor pool based on the results of clinical evaluation and laboratory tests consisting of polymerase chain reaction based mutational analysis for cystic fibrosis carrier status, cytogenetic analysis for karyotype, enzymatic assay for Tay-Sachs disease carrier status, and complete blood count and hemoglobin electrophoresis.

RESULT(S)

Eight (11%) of 73 oocyte donor candidates were excluded from the donor pool because of a potentially serious genetic finding. Cystic fibrosis mutations were identified in 5 candidates (7%), abnormal karyotypes were found in 2 (3.5%), and an autosomal dominant skeletal dysplasia was identified in 1 (1.4%).

CONCLUSION(S)

A significant proportion of women who present as candidates for oocyte donation are inappropriate for donation because of their genetic history or genetic testing results. A thorough genetic evaluation, including a history and laboratory screening, is essential to any oocyte donation program to maximize positive outcomes in pregnancies achieved through assisted means.

Laparoscopy for pelvic pain in the Mayer-Rokitansky-Kuster-Hauser syndrome. A case report

BACKGROUND

The Mayer-Rokitansky-Kuster-Hauser (MRKH) syndrome occurs in 1 of every 4,000-5,000 female births. It is characterized by normal external genitalia, an absent vagina, absent or rudimentary uterus, and normal fallopian tubes and ovaries. When associated with a rudimentary uterine horn, cyclic catamenial pelvic pain may result. The standard procedure for pain relief has been removal of the uterine horn by laparotomy.

CASE

A rudimentary uterine horn was diagnosed in a woman with MRKH syndrome who developed monthly severe pelvic pain. Removal of the structure was performed via laparoscopy. The patient had complete resolution of her pain.

CONCLUSION

As an alternative to laparotomy, laparoscopic resection of a rudimentary horn in patients with MRKH syndrome is both feasible and beneficial in the treatment of pelvic pain.

Mature cystic teratoma: a clinicopathologic evaluation of 517 cases and review of the literature

OBJECTIVE

To evaluate the clinical and pathologic presentation of mature cystic teratomas and the trends in management over a 14-year study period.

METHODS

Tumor registry data and medical records between January 1, 1975 and December 31, 1989 were analyzed with respect to patient age, tumor size, bilaterality, malignant transformation, and treatment.

RESULTS

Five hundred seventy-three tumors were removed from 517 patients. The median and mean (+/- standard deviation) age was found to be 30 and 32 +/- 11.3 years, respectively. Three hundred ten (60%) of the patients were asymptomatic. The mean tumor size was 6.4 +/- 3.5 cm. The bilaterality rate was 10.8%. The rate of torsion was 3.5%; larger tumors underwent torsion more frequently than smaller tumors (P = .029). The rate of malignant transformation was 0.17%. The mean cyst diameter for patients undergoing cystectomy was 5.7 +/- 2.4 cm; for oophorectomy, 8.0 +/- 4.1 cm; and for hysterectomy, 6.1 +/- 3.8 cm. Oophorectomies were performed for larger tumors when compared to cystectomies (P = .01). The number of hysterectomies was stable throughout the study period, whereas the number of oophorectomies decreased and the number of cystectomies increased markedly. Contralateral ovarian biopsy was common (48.5%) early in the study period. By 1989, the biopsy rate was less than 1%.

CONCLUSIONS

We found the prevalence rates of symptomatic tumors, torsion, and malignant degeneration to be less than those previously reported by most other investigators. In addition, there has been an important change over the past 14 years in the management of these neoplasms, with an increased tendency for ovarian preservation, as evidenced by the more frequent use of cystectomy and a decrease in contralateral ovarian biopsy.

Opening of the mouse zona pellucida by laser without a micromanipulator

A contact-free laser system is described for ablation of the embryonic mouse zona pellucida using a pulsed excimer 308 nm laser. Effects on further embryonic development were evaluated. Zonae of 8- to 16-cell mouse embryos were either lased (n = 189), zona-drilled with acidified Tyrode's solution (n = 183) or left zona-intact (n = 188). Blastocyst formation (99-100%) was similar in the three groups. Hatching occurred earlier in lased embryos compared to those of the control group. These blastocysts hatched through the laser ablated area. Significantly more embryos were hatching on day 4 in the conventionally drilled group when compared to the laser treated group (50% versus 24% respectively). On day 7 of development, significantly (P < 0.05) more embryos conventionally zona-drilled (37%) were intact than those which were previously laser treated (10%). Abnormal development was also noted in a small group of embryos which were lased just on the outside of the zona in comparison to 1/3 of an embryonic width away from the zona. The current results suggest that apparently precise zona laser ablation with an excimer laser at 308 nm may have potential adverse effects which may only be manifested after a prolonged period of culture past the cavitation stage. However, implantation rates of morphologically normal laser abalated embryos were not impaired when compared to control embryos.

Microinjection of FITC-dextran into mouse blastomeres to assess topical effects of zona photoablation

The objective of the current experiments was to investigate whether all or only some blastomeres from precompacted mouse embryos were affected by zona photoablation. The microbeam of xenon chloride excimer laser (308 nm) was guided through an inverted microscope (non-contact system). Topical effects of lasing were determined by microinjection of a vital fluorescent dye of high molecular weight (fluorescein isothiocyanate [FITC] dextran) into the cell immediately adjacent to the site of zona photoablation. This dye is only passed onto daughter blastomeres and therefore allows study of specific cell lines. Embryonic growth was assessed following cell separation at the morula and blastocyst stage. Four-cell embryos treated with the laser had significantly fewer cells 12 h after zona photoablation than control embryos. A similar effect was noted after 24 h between dye injected embryos and those injected and lased simultaneously, indicating potential toxic effects of the laser treatment on the embryo. Effects on the blastomere closest to the site of ablation were evaluated by calculating the ratio of dyed cells to the total number of cells at specific time intervals. The ratios were similar in the dye and laser+dye groups of treated 4-cell embryos 36 h after treatment (0.22 and 0.23, respectively), indicating that the dye was still present in approximately 25% of the cells and that the negative effect of photoablation was evenly distributed among the blastomeres. It is concluded that zona photoablation may have long-term detrimental effects of a non-topical nature on precompacted mouse embryos in spite of the apparent precision of the laser spot size.