[A rare splenic lesion, the splenoma or splenic hamartoma]. / Une lésion rare de la rate, le splénome ou hamartome splénique.

We report a new case of splenoma in a previously healthy adult. A 52-year-old man was admitted for a splenomegaly with thrombocytopenia. The computed tomographic scan showed a tumor which measured 56 mm in diameter. A splenectomy was performed. Histologic examination of the splenectomy specimen revealed a splenoma. Splenoma or splenic hamartoma is a rare primary splenic tumor most often incidentally discovered, radiologically. It can also meet in a particular pathological context, evoking more a coexistence rather than an association or a complication, underlying the role of the pathologist in its diagnosis.

[The use of double J stent for prevention of urological complications in kidney transplants]. / Empleo del catéter doble J para la prevención de las complicaciones urológicas en el trasplante renal.

OBJECTIVE: To analyze the impact of the use of the double J stent in the incidence of urological complications, like fistula urinary and ureteral obstruction in kidney transplants. MATERIALS AND METHODS: Between August 2003 and December 2005, 59 adult recipients underwent renal transplant. A retrospective study was conducted on two groups of patients: Group A with double J stent and group B without it. We reviewed the urological complications: fistula, ureteral obstruction and urinary tract infection. RESULTS: Group A: One ureteral obstruction and two urinary fistulas (7%) were developed in this group. 13 patients (46%) had a positive urinary culture. In only one case was necessary to retire the double J stent because of ureteral obstruction. Group B: Four patients (13%) developed ureteral obstruction and another five (16%) developed urinary fistula. 9 patients (29%) had a positive urinary culture. CONCLUSION: The routine insertion of a double J stent in kidney transplants reduces the number of early complications urinary fistula and ureteral obstructions.

[Contact tracing in a case of tuberculosis in a health care worker]. / Investigations autour d'un cas de tuberculose d'un soignant.

INTRODUCTION: Tuberculosis is a public health problem, of which the nosocomial transmission from a health care worker to patients has not been well documented. OBSERVATIONS: A Senegalese surgeon aged 32 was admitted to hospital on account of deterioration in his general health. He was found to have sputum positive tuberculosis and received standard treatment. We report the strategy employed for tracing the contacts of this health care worker. Of a total of 185 members of staff (permanent and temporary) and 91 patients who had been in contact with the index case, 180 (97.3%) and 71 (78%) respectively were screened. Of the 251 subjects screened, 5 staff (2.8%) and 11 patients (15.4%) showed evidence of latent tuberculous infection and 6 were treated. In total 97.3% of staff exposed were screened at the beginning of the study and 63% were reviewed at 3 months as opposed to 78% and 53% for the patients. CONCLUSION: This study shows poor compliance with the visit 3 months after exposure and the need to standardise the procedures in order to improve the screening and follow up of contacts.

[Waldenström's macroglobulinemia with an uncommon presentation]. / Macroglobulinémie de Waldenström: à propos d'une présentation clinicobiologique peu commune.

Waldenström's macroglobulinemia is a rare disease with an indolent clinical course. The median age of the affected patient is 65 years. Nevertheless, we report a case of Waldenström's macroglobulinemia revealed by a splenomegaly and severe pancytopenia, in a 51-year-old man without previous medical history. According to the recent consensus recommendations for the clinicopathological definition of Waldenström's macroglobulinemia, diagnosis was made through morphological and immunophenotypic data of medullary cells. The reduced survival of the patient is associated with the importance of the cytopenia.

[A 7-year survey of strains identified in blood cultures in a clinical hematology unit]. / Etude sur sept ans des isolats d'hémocultures dans un service d'hématologie clinique.

GOAL: This study had for aim to analyze the epidemiology of strains identified in blood cultures (hôpital d'instruction des armées Percy, Clamart, France, hematology unit) to compare the rate of identified micro-organisms with literature data, and to search for a possible correlation between antibiotherapy management and evolution of resistance profiles. MATERIAL AND METHODS: All the micro-organisms (N = 690) collected over seven years (January 1996 to December 2002), from blood cultures of hospitalized patients in conventional and sterile sector were studied. RESULTS: Gram positive cocci rate (GPC) was 62.6% and Gram negative bacilli (GNB) 31.3%. Evolution in time showed a decrease of GPC and an increase of GNB, notably the non fermenting Gram negative bacilli, leading to an equal rate by 2001-2002. The most frequently identified species were Staphylococcus epidermidis (36.4%), Escherichia coli (8.7%), Pseudomonas aeruginosa (6.8%), and Staphylococcus aureus (4.9%). The rate of methicillin-resistant staphylococci was 63.6%. Fifty-five percent of E. coli strains had a penicillinase phenotype. Pseudomonas aeruginosa resistance was 8.5, 8.5, 6.4 and 8.5%, respectively for ceftazidime, piperacillin-tazobactam, imipenem, and amikacin. CONCLUSION: This study showed a tendency to inversion of former bacteremia epidemiology with increasing negative Gram bacilli. It justifies the antibiotherapy protocols adopted in the hematology unit.

[Blood transfusion security: one train may conceal another!]. / Sécurité transfusionnelle: un train peut en cacher un autre!

The discovery of antibodies with specificities that are directed toward antigens of high prevalence is a difficult situation to manage in emergency blood transfusion. The reactions they produce interfere with the identification of reactions due to other, clinically significant antibodies. We report a case which illustrates this problem in terms of transfusion safety and time to carry out the tests.

[Transfusional record and blood grouping methods: essential factors of transfusion safety]. / Dossier transfusionnel et techniques de groupage sanguin: éléments essentiels de la sécurité transfusionnelle.

The clinical and biological control of the whole transfusion process is a major preoccupation for everyone dealing with blood transfusion. Specially when the patient is a female recipient or belongs to a group with a high prevalence of alloimmunisation. This case report points out the outstanding importance of the immune compatibility, which must be strongly maintained to prevent any harmful consequences. The transfusional record transmission and a simple and sensitive blood grouping test are essential to increase transfusion safety.

Exponential growth of Escherichia coli B/r during its division cycle is demonstrated by the size distribution in liquid culture.

The Collins and Richmond equation was used to analyze the growth of individual bacterial cells. Birth size was derived from the size of deeply constricted cells in the sample. The analysis was applied to normalized and pooled data from electron micrographs of Escherichia coli showing that cellular length, surface, and volume do not grow linearly as reported before. We present evidence that bacteria grow exponentially during the division cycle, which is consistent with previous proposals. Our results confirm previous incorporation studies that demonstrate basically exponential growth patterns for cell mass during the division cycle.

Plasmolysis during the division cycle of Escherichia coli.

Cells of Escherichia coli were plasmolyzed with sucrose. They were classified according to length by way of electron micrographs taken from samples prepared by agar filtration. The percentage of plasmolyzed cells increased about two- and threefold between mean cell sizes of newborn and separating cells. However, dividing cells were less frequently plasmolyzed than nondividing cells of the same length class. Analysis of cell halves (prospective daughters) in dividing cells showed that they behaved as independent cellular units with respect to plasmolysis. The results indicate that compressibility of the protoplast (given a certain plasmolysis space) is inversely related to cell size. That a dividing cell does not react as one osmotic compartment to osmotic stress may suggest that cell size-dependent strength of the cell membrane-cell wall association, rather than variation in turgor, plays a role during the cell division cycle.

Generality of the growth kinetics of the average individual cell in different bacterial populations.

The kinetics of growth of all the cells in a population is reflected in the shape of the size distribution of the population. To ascertain whether the kinetics of growth of the average individual cell is similar for different strains or growth conditions, we compared the shape of normalized size distributions obtained from steady-state populations. Significant differences in the size distributions were found, but these could be ascribed either to the precision achieved at division or to a constriction period which is long relative to the total cell cycle time. The remaining difference is quite small. Thus, without establishing the pattern itself, it is concluded that the basic course of growth is very similar for the various Escherichia coli strains examined and probably also for other rod-shaped bacteria. The effects of differences in culture technique (batch or chemostat culture), growth rate, and differences among strains were not found to influence the shape of the size distributions and hence the growth kinetics in a direct manner; small differences were found, but only when the precision at division or the fraction of constricted cells (long constriction period) were different as well.

Effects of temperature on the size and shape of Escherichia coli cells.

Two substrains of Escherichia coli B/r were grown to steady-state in batch cultures at temperatures between 22 and 42 degrees C in different growth media. The size and shape of the cells were measured from light and electron micrographs and with the Coulter channelizer. The results indicate that cells are shorter and somewhat thicker at the lower temperatures, especially in rich growth media; cell volume is then slightly smaller. A lower temperature was further found to increase the relative duration of the constriction period. The shapes of the cell size distributions are indistinguishable, indicating that the pattern of growth of the cells is the same at all temperatures. The adaptation of the cells to a temperature shift lasted several generations, indicating that the morphological effects of temperature are mediated by the cell's physiology.

On the precision and accuracy achieved by Escherichia coli cells at fission about their middle.

Length and width of each of the prospective siblings of constricted Escherichia coli cells from different strains and culture conditions were measured from electron micrographs. The data were statistically analyzed to investigate how equally the length and volume of one cell was divided into two. The analysis showed that, for all cultures. bipartition is unbiased or very nearly so, i.e. sibling cells were on the average equally long and large. The precision of bipartition attained by the cells was usually high; it was related to the average cell shape (length/width): slender E. coli cells divided into two less precisely than squat cells, Absolute size, growth rate and strain specificity affected the precision of bipartition only indirectly, i.e. in as much as they influenced cell shape.

Changes in cell diameter during the division cycle of Escherichia coli.

Extensive measurements of steady-state populations of several Escherichia coli strains have consistently indicated that cell diameter decreases with increasing cell length. This was observed both after electron microscopy of air-dried cells and after phase-contrast microscopy of living cells. The analysis was made by considering separately the unconstricted cells and three classes (slight, medium, and deep) of constricted cells in the population. During slow growth, cells with the average newborn length were up to 8% thicker than unconstricted cells twice as long. This decrease in diameter is less at higher growth rates. Despite the small changes and the large variation of the diameter in any particular length class, significant negative correlations between diameter and length were obtained. Cell diameter increases again at the end of the cell cycle as indicated by an increase of average diameter in the three consecutive classes of constriction.