Tehran University Medical Journal

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Background: Simple bone cyst is a common benign lesion in the proximal humerus, especially in prepubertal children. Up to 75 percent of patients with the bone cyst have a pathologic fracture and the most significant complication is recurrent pathologic fracture. Since the process of spontaneous healing of these fractures is rare, treatment is required. Ideal treatment for simple bone cyst should stabilize pathologic fractures, assist healing and provide a quick return to normal activity with reduced complication and recurrence.
Methods: In this descriptive case series study, 24 patients with simple bone cysts of the humerus were selected for retrograde flexible intramedullary nailing from the lateral cortex of the distal humerus, since 2000 to 2005 at Imam Khomeini Hospital, Tehran. The mean age of the patients was 14.4 years, ranging from 6-39 years. Results were evaluated by plain radiography using the classification system of Capanna et al.
Results: The mean duration of follow up for 23 of the patients was 31 (9-51) months. One patient with short-term of follow-up was excluded. Of these patients, 91.3% were healed either completely (65.2%) or with residual minor defect (26.1%). Only one cyst (4.3%) persisted with no response to treatment and one patient (4.3%) had a recurrence of the cyst. However, there was no instance of recurrent pathologic fracture among these patients.
Conclusion: This study shows that flexible intramedullary nailing is an effective treatment for humeral simple bone cysts that reduces the chance of complication, recurrence of cyst or pathologic fracture. This technique provides sufficient stability for quick return to normal activity.

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Background: Bacillus cereus spores distribute widely in nature and can be isolated from different kinds of foods. This bacterium can produce diarrhea and emetic enterotoxins and syndromes. As infants are known to be more susceptible to B. cereus infection due to their incomplete intestinal flora and fast growth of this bacterium during consumption, it is very important to investigate the presence of B. cereus in infant formula and possible pathogenicity of this microorganism in infants. 

Methods: In this study, 60 samples of infant formula were examined for the presence of B. cereus. From a 1/10 dilution of each sample, a total amount of 1 ml was inoculated onto four phenol red agar plates containing mannitol, egg yolk emulsion and polymyxin B sulfate. The plates were incubated at 30°C for 24 hours. Confirmation tests were then performed on suspected colonies.

Results: Among the 60 samples, 11 samples had more than 10 cfu/g, four of which contained more than 102 cfu/g. The other 49 samples showed less than 10 cfu/g of B. cereus. 

Conclusions: We suggest that for infant formula the maximum microbial limit be reduced to less than 10 cfu/g to control B. cereus contamination and to prevent infection in infants. For this purpose, infant formula should be tested by the method and confirmation tests used in this study. In addition, susceptibility to penicillin, ß-hemolysis and growth rate at 45ºC could also be performed.