Expression of myogenic regulatory proteins (myogenin and MyoD1) in small blue round cell tumors of childhood

The distinction of rhabdomyosarcoma (RMS) from other small blue round cell tumors of childhood, such as Ewing's sarcoma/peripheral primitive neuroectodermal tumor (pPNET) and neuroblastoma, continues to present a diagnostic challenge to pathologists. The recent recognition of the master role of myogenic regulatory proteins in skeletal muscle commitment and differentiation, and the availability of monoclonal antibodies to two of them (myogenin and MyoD1), has prompted us to test their diagnostic utility in routinely processed, formalin-fixed, and deparaffinized tissue. Preliminary studies had demonstrated that, with the use of heat-induced epitope retrieval techniques, expression of myogenin and MyoD1 could be documented specifically in nuclei of fetal skeletal muscle by the respective antibodies. We performed a retrospective immunohistochemical analysis on 72 cases of small blue round cell tumors, including 33 RMSs, 1 metastatic myogenous Wilms' tumor, 26 Ewing's sarcomas/pPNETs, and 12 neuroblastomas. Nuclear expression of myogenin and MyoD1 were both found in 30/33 non-overlapping cases of RMS, with no significant differences in the sensitivity with respect to histological subtypes, and in 1/1 case of myogenous Wilms' tumor. None of the neuroblastomas or Ewing's sarcomas/pPNETs demonstrated positive nuclear staining with either antibody. However, most of the neuroblastomas, and occasional Ewing's sarcomas/pPNETs, showed variable fibrillary, cytoplasmic immunoreactivity with antibody to MyoD1. We conclude that, with the use of microwave-based epitope retrieval, antibodies to myogenin and MyoD1 are both useful markers for the identification of RMS among other small blue round cell tumors of childhood, but antibodies to myogenin have technical advantages over those to MyoD1, as the latter may cross-react with an unknown cytoplasmic antigen in non-muscle cells and tumors.

Endophthalmitis and orbital cellulitis after radial keratotomy

PURPOSE

To report the findings concerning three patients with endophthalmitis and one with panophthalmitis and orbital cellulitis radial keratotomy surgery.

METHODS

One man referred with panophthalmitis and orbital cellulitis and three women referred with endophthalmitis were treated.

RESULTS

After radial keratotomy surgery, during which no microperforation or macroperforation had been reported, a severe Pseudomonas panophthalmitis and orbital cellulitis developed in the man. All vision was lost in that eye. Staphylococcus epidermidis endophthalmitis developed in one woman, Streptococcus pneumoniae endophthalmitis in the second woman and Pseudomonas endophthalmitis in the third woman, after undergoing radial keratotomy procedures during which microperforations occurred. In the latter patient, bilateral simultaneous surgery was performed, but only one eye became infected. The latter two infections resulted in light perception and hand motion vision respectively. In three cases, an initial keratitis was located in the inferior cornea.

CONCLUSIONS

Severe bacterial endophthalmitis can occur after radial keratotomy surgery, even in the absence of microperforation during the procedure. Any evidence of postoperative keratitis must be regarded seriously and treated aggressively. Despite use of this approach, the effect on final visual acuity can be devastating.

TB exposure: are you prepared?

1. The elderly have the highest case rates for TB disease. 2. Residents need to be screened for TB infection on admission with a Mantoux skin test. 3. Employees need to be screened for TB by the Mantoux skin test on hire and annually. 4. A chest x-ray is not adequate to screen for TB infection.

Day care and the incidence of otitis media in young children

OBJECTIVE

This study assesses whether day care is a significant risk variable for otitis media in children younger than 2 years in the United States after controlling for the number of children in the day care group.

DESIGN

The computerized data source used is the 1988 Child Health Supplement (N = 17,110) of the National Health Interview Survey (NHIS-CH).

SETTING

The NHIS-CH data is a multistage probability sample with clustering and stratification. It represents the civilian, noninstitutionalized population of the United States.

PARTICIPANTS

The NHIS-CH sample consists of one randomly selected child from each NHIS household containing a child younger than 18 years. The overall response rate for the NHIS-CH was approximately 90%. For this analysis the focus is on children younger than 2 years (N = 2294).

MAIN OUTCOME MEASURES

The NHIS-CH includes a direct questioning of an adult member of the household, usually the mother, about whether the child has ever had frequent or repeated ear infections.

RESULTS

After controlling for the total size of the day care group for children younger than 12 months, the previously established relationship between attending a day care center and frequent ear infections is reduced from an odds ratio of 3.17 (95% confidence interval, 1.50 to 6.71) to an odds ratio of 1.34 (not significant; p = 0.60).

CONCLUSION

The total size of the day care group is an important intervening variable in the relationship between attending day care and frequent ear infections for children younger than 12 months. The size of the day care group rather than the day care per se is the primary "modifiable risk variable" for many working parents.

Day Care and the Incidence of Otitis Media in Young Children

OBJECTIVE: This study assesses whether day care is a significant risk variable for otitis media in children younger than 2 years in the United States after controlling for the number of children in the day care group.

DESIGN: The computerized data source used is the 1988 Child Health Supplement ( N = 17,110) of the National Health Interview Survey (NHIS-CH).

SETTING: The NHIS-CH data is a multistage probability sample with clustering and stratification. It represents the civilian, noninstitutionalized population of the United States.

PARTICIPANTS: The NHIS-CH sample consists of one randomly selected child from each NHIS household containing a child younger than 18 years. The overall response rate for the NHIS-CH was approximately 90%, For this analysis the focus is on children younger than 2 years ( N = 2294).

MAIN OUTCOME MEASURES: The NHIS-CH includes a direct questioning of an adult member of the household, usually the mother, about whether the child has ever had frequent or repeated ear infections.

RESULTS: After controlling for the total size of the day care group for children younger than 12 months, the previously established relationship between attending a day care center and frequent ear infections is reduced from an odds ratio of 3.17 (95% confidence interval, 1.50 to 6.71) to an odds ratio of 1.34 (not significant p = 0.60).

CONCLUSION: The total size of the day care group is an important intervening variable in the relationship between attending day care and frequent ear infections for children younger than 12 months. The size of the day care group rather than the day care per se is the primary “modifiable risk variable” for many working parents.

"To grandmother's house we go": health and school adjustment of children raised solely by grandparents

This study uses data from the 1988 National Children's Health Supplement (N = 17,110) to the National Health Interview Survey to examine the health and school adjustment of children raised solely by grandparents. We find that these children fare quite well relative to children in families with one biological parent present, a category which includes both single-parent and blended families. Furthermore, children raised solely by grandparents are not significantly different, except for academic performance, from children raised in traditional families where two biological parents are present.