Cell motility as an energy minimization process.

The dynamics of active matter driven by interacting molecular motors has a nonpotential structure at the local scale. However, we show that there exists a quasipotential effectively describing the collective self-organization of the motors propelling a cell at a continuum active gel level. Such a model allows us to understand cell motility as an active phase transition problem between the static and motile steady-state configurations that minimize the quasipotential. In particular, both configurations can coexist in a metastable fashion and a small stochastic disorder in the gel is sufficient to trigger an intermittent cell dynamics where either static or motile phases are more probable, depending on which state is the global minimum of the quasipotential.

Antifungal susceptibility of bloodstream Candida isolates in Sfax hospital: Tunisia.

UNLABELLED: Invasive candidiasis has emerged as an important nosocomial infection, causing significant morbidity and mortality especially among critically ill patients. The aim of our study was to determine specie distribution and resistance profiles of Candida species isolated from blood cultures. MATERIALS AND METHODS: We conducted a retrospective study of all episodes of candidemia diagnosed in our laboratory from January 2006 to May 2009. The susceptibility to antifungal agents of all Candida isolates was tested by using a Sensititre(®) YeastOne panel. RESULTS: A total of 130 Candida isolates were recovered from blood cultures. Candida tropicalis was the most frequent specie (37.7%), followed by C. albicans (22.3%), C. glabrata (19.2%), and C. parapsilosis (12.2%). All the isolates were inhibited by ≤1 µg/ml of amphotericin B and ≤2 µg/ml of caspofungin. For fluconazole, 7.3% of clinical isolates were resistant. It was most active against C. parapsilosis (100% susceptible), C. albicans (95.8% susceptible), and C. tropicalis (94% susceptible). All of the fluconazole-susceptible isolates were susceptible to voriconazole, as were 83.3% of the fluconazole-susceptible-dose-dependent isolates. Among fluconazole-resistant isolates, 85.7% were susceptible to voriconazole. CONCLUSIONS: In our institution, C. tropicalis was the most frequent specie isolated from the bloodstream. Caspofungin had an excellent in vitro activity against Candida isolates and was the drug of choice among fluconazole-resistant isolates.

Candida dubliniensis: first identification in Sfax Hospital, Tunisia.

Candida dubliniensis, a newly described fungal pathogen associated mainly to immunocompromised host's infection, is phenotypically closely related to C. albicans. In this study, we report for the first time, isolation and identification, in Tunisia, of 14 isolates of C. dubliniensis from 12 human immunodeficiency virus-negative patients hospitalised in the intensive care unit (ICU) at Habib Bourguiba Sfax Hospital. Our study was firstly based on the failure to grow at 45 degrees C. This presumptive identification was completed by other tests: chlamydospore production, culture on Candiselect4 (Bio-Rad) and the commercial test Bichro-Dubli fumouze, which specifically identify C. dubliniensis. The confirmation of the discrimination between both species was performed by PCR, targeting the hyphal wall protein (HWP1) gene. The recovery of C. dublinensis by routine laboratory diagnosis is recommended for elucidating the epidemiology of this novel pathogen.

Safety and efficacy of colistin compared with imipenem in the treatment of ventilator-associated pneumonia: a matched case-control study.

OBJECTIVE: Our study aimed to determine the efficacy and safety of colistin in the treatment of ventilator-associated pneumonia (VAP) caused by pan-drug-resistant Pseudomonas aeruginosa or Acinetobacter baumanii. DESIGN: Pairwise, retrospective exposed-unexposed study. SETTING: Combined medical and surgical intensive care unit of Habib Bourguiba University Hospital (Sfax, Tunisia). PATIENTS: Sixty patients with VAP caused by pan-drug-resistant A. baumanii or P. aeruginosa matched to 60 controls with VAP caused by A. baumanii or P. aeruginosa susceptible to imipenem. All patients had normal renal function at the onset of antibiotic therapy. INTERVENTIONS: Case patients were treated by colistin intravenously and control patients were treated by imipenem intravenously. MEASUREMENTS AND RESULTS: Baseline characteristics were similar between the colistin and imipenem groups. The mean duration of antibiotic therapy for VAP was 9.5+/-3.8 days (range 5-22 days) with colistin and 8.9+/-2.8 days (range 5-20 days) with imipenem (p=0.32). A favorable clinical response to antibiotic therapy for VAP occurred in 45 patients (75%) in the colistin group and in 43 patients (71.7%) in the imipenem group (p=0.68). The time to resolution of infectious parameters after the initiation of antibiotic therapy was not statistically different between the two groups. During the antibiotic course, none of the patients in either group developed renal failure. CONCLUSIONS: We conclude that colistin can be a safe and effective option in the treatments of VAP caused by pan-drug-resistant P. aeruginosa or A. baumanii.

[Thrombotic microangiopathies. Incidence, pathogenesis, diagnosis, treatment and prognosis]. / Les microangiopathies thrombotiques. Incidence, physiopathologie, tableau clinique, prise en charge thérapeutique et pronostic.

INTRODUCTION: The objective of this work was to review current data about the pathophysiology, clinical features, and treatment of thrombotic microangiopathies. CURRENT KNOWLEDGE: Thrombotic microangiopathies are microvascular occlusive disorders characterized by systemic or intrarenal aggregation of platelets, thrombocytopenia, and mechanical injury to erythrocytes. In thrombotic thrombocytopenic purpura, systemic microvascular aggregation of platelets causes ischemia in the brain and other organs. In the hemolytic-uremic syndrome, platelet-fibrin thrombi occlude predominantly the renal circulation. Thrombotic microangiopathy is a rare disorder whose varied clinical manifestations result from the formation of platelet-rich thrombi within the microvasculature and consequent tissue ischemia. The clinical features are acute renal failure, microangiopathic hemolytic anemia and thrombocytopenia. This diagnosis is of considerable importance because of the possible fulminant clinical course. Some atypical forms may be unrecognized. Plasma exchange is the current reference treatment of thrombotic thrombocytopenic purpura. However, in the light of recent publications, either infusions of concentrates of purified enzyme or more intensive immunosuppressive therapy would be more specific.

[Prognostic factors of pneumococcal meningitis. Retrospective study of 31 cases]. / Facteurs de pronostic des méningites à pneumocoque. Etude rétrospective de 31 cas.

AIM: Our aim was to study the susceptibility of Streptococcus pneumoniae to antibiotics in patients with pneumococcal meningitis and to search for the prognosis factors in those patients. METHODS: We have studied retrospectively 31 cases of pneumococcal meningitis. Comparaisons were performed with univariate analysis. RESULTS: The mean age was 36.7 +/- 20.5 years (ranged: 9 and 78 years). The sex ratio was 3,4. The susceptibility of Streptococcus pneumoniae to penicillin G was affected in 10 cases (33% of isolated pneumococcus. The MIC to penicillin G was > or =2 in only one case. The hospital mortality was 26% (8/31). With univariate analysis, factors associated with death were: age > or =55 years (Ss p= 0,006, OR: 17.2 IC95%: 2.3-134), albuminorachie > or = 7 g/l (p = 0.002, OR: 22; IC95%: 1.9-2.51), shock (p = 0.031, OR: 6.7; IC95%: 1.05-42) and Glasgow Coma Score (GCS) < or =8 (p = 0.001, OR: 20; IC95%: 2.68-149). CONCLUSION: No susceptibility to penicillin G is not associated with a worse outcome in patients with pneumococcal meningitis. An age > or =55 years, albuminorachie > or =7 g/l shock and Glasgow Coma Score < or =8 at admission were determinant of the prognosis in our study.

[Traumatic unilateral renal artery thrombosis and protein C deficiency. A case report]. / Thrombose post-traumatique de l'artère rénale et déficit en protéine C. A propos d'un cas.

Post traumatic renal artery thrombosis is rarely described in the literature. This pathology can result from stretch injury to inelastic intima of the renal artery, or by the direct flow to the abdomen causing compression injury to the renal artery against the vertebral column. However, the association of this pathology with hematologic diseases (in particular protein C deficit) was never described. We report an observation of a 28-year-old man with an uneventful history who was admitted to the intensive care unit for traumatic head injury associated with post traumatic renal artery thrombosis requiring nephrectomy. The etiologic investigation of this thrombo-embolic complication reveals a protein C deficit. Our patient was improved under treatment. This original observation confirms that post traumatic renal artery thrombosis can be associated with hematologic diseases (in particular protein C deficit).

[Acute fatty liver of pregnancy. About 22 cases]. / Stéatose hépatique aiguë gravidique. A propos de 22 cas.

OBJECTIVE: To report the clinical experience, biochemical findings, complications and maternal outcome in patients with acute fatty liver of pregnancy (AFLP). PATIENTS AND METHODS: Retrospective study over a period of 11 years (1993-2003). The diagnosis of AFLP was confirmed by liver biopsy in 15 women. However, in 7 women a medical committee that took into account clinical symptoms, and laboratory findings assessed the diagnosis. RESULTS: Were included in this study, 22 women with a mean age of 30+/-5.4 years. Only 22.7% of cases were primigravid. The mean gestational age was 36+/-2.76 weeks (range 31-41 weeks). The fetus was a male infant in 75% of cases. Ten women were admitted in the hospital without jaundice. However 15 women had developed an icterus since their hospital admission or during ICU stay. The mean SAPS II on the ICU admission was of 24.86+/-11.2 points. Biological disturbances observed were mainly: liver cytolysis in 91% of cases, a trend to hypoglycaemia in 86%, a hypoprotidemia in 66.7% and CIVD in 32%. During their ICU stay, 19 women (86.4%) developed one or several organ failures associated to the hepatic failure and 18 women required blood transfusion. After an average stay of 7.5 days, evolution was marked by the death of seven patients (31.8%). Factors correlated with a poor prognosis were: the delay of medical consultation, the development of jaundice, the development of encephalopathy, respiratory or a circulatory failure. DISCUSSION AND CONCLUSION: AFLP is a rare but life-threatening complication. Furthermore AFLP shares features with other more common and less perilous illnesses. An early diagnosis and appropriate therapy of this pathology should improve the poor prognosis in our country.

[Uterine sarcomas: clinical and therapeutic aspects (10 cases)]. / Sarcomes utérins: aspects cliniques et thérapeutiques. A propos de 10 cas.

PURPOSE: Uterine sarcomas are rare tumours characterized by clinical and histopathological diversity and poor prognosis. We analyzed diagnostic, prognostic and therapeutic difficulties encountered with these tumors by insisting on the importance of early diagnosis. PATIENTS AND METHODS: From 1997 to 2004 ten patients with uterine sarcoma who underwent surgery in the obstetrics and gynecology unit at the Tunis maternity center were included in this retrospective study. The tumors were classified at the time of diagnosis using the FIGO staging system. The histological diagnosis was based on the WHO classification. RESULTS: There were 5 cases of leiomyosarcoma, 2 cases of carcinosarcoma, 2 cases of endometrial stromal sarcoma and 1 adenosarcoma. There were four cases of stage I, two cases of stage II, two cases of stage III and two of stage IV tumors. The diagnosis of uterine sarcoma was strongly suspected and proved before the initial operation in 20% of cases and during this operation in 60% of cases. Diagnosis was only established at the histological exam in two cases. Total hysterectomy with bilateral salpingo-oophorectomy was performed in 90% of patients. Radiation therapy was performed in four. Chemotherapy was delivered in two patients. After an average of four years five patients were in remission, three had died and two were lost to follow-up. CONCLUSION: Early preoperative or intra-operative diagnosis is essential while awaiting for more effective chemotherapy protocols or therapeutic strategies.

[Thrombotic microangiopathies in the intensive care unit]. / Les microangiopathies thrombotiques en réanimation.

OBJECTIVES: To analyze the clinico-biological manifestations, identify the causes and evaluate the outcome of patients with severe thrombotic microangiopathies admitted in a Tunisian intensive care unit. METHODS: Retrospective study over a period of 10 years (1995-2004) in an intensive care unit. RESULTS: Were included in this study 9 cases with a mean age of 29.2+/-9 years (range 15-44 years). Fever was observed in 5 patients, neurological impairment in 5 and digestive manifestations in 6. Haemolytic anaemia, thrombocytopenia and acute renal failure were observed in 100% of the cases. In our study, the aetiologies of thrombotic microangiopathies were: complicated pregnancy in 6 cases, systemic lupus erythematosus in 1 case. In contrast, no aetiology was found in 2 patients. Plasma exchange was performed in 5 patients, while 4 patients received only plasma infusion. After an average stay of 18+/-12.5 days, evolution was marked by the death 3 patients. CONCLUSION: The incidence of severe thrombotic microangiopathies is rare in Tunisian ICU. The clinical manifestations are not specific. Despite the improvement in the outcome by exogenous plasma supply, thrombotic microangiopathies with severe organ dysfunctions leading to hospitalization in the intensive care unit are associated with a high mortality rate.

[Posttraumatic meningitis: incidence, bacteriology, and outcomes]. / La meningite post-traumatique: incidence, microbiologie et pronostic.

BACKGROUND AND PURPOSE: The aim of our study was to search for the incidence, the responsible organisms and the favoring causes of death of post-traumatic meningitis (PTM). METHODS: This retrospective study was conducted over a seven-year period (January 1st, 1996 - December 31, 2002) in the ICU and the neurosurgery department of the Habib-Bourguiba University Hospital, Sfax, Tunisia. RESULTS: Over the study period, 38 patients presented PTM (0.96% of patients hospitalized for head injury), 92% of them had received antibiotic prophylaxis on admission. Mean time between head injury and the diagnosis of PTM was 9+/- 8 days (range: 2-34 days). The most common isolated organisms were multidrug resistant A. baumanii, and K. pneumoniae and reduced susceptibility S. pneumoniae. Factors predictive of prognosis in the 14 days following the diagnosis of meningitis were Glasgow coma score (GCS) on the day of diagnosis of PTM, absence of nuchal rigidity, CSF protein, CSF/blood glucose ratio, and S. pneumoniae as the causal agent of PTM. CONCLUSIONS: Antibioprophylaxis in patients with head trauma must be avoided to prevent the emergence of multidrug resistant bacteria when PTM occurs. GCS on the day of diagnosis of PTM, CSF protein concentration, CSF/blood glucose ratio, and S. pneumoniae as the causal agent of PTM are predictive factors of mortality of patients with PTM.

[Up-to-date on the HELLP syndrome (Hemolysis, Elevated Liver enzymes and Low Platelets)]. / Actualité sur le syndrome HELLP (Hemolysis, Elevated Liver enzymes and Low Platelets).

HELLP syndrome is an acronym for Hemolysis, Elevated Liver enzymes and Low Platelets. It is generally considered in the literature as a particular clinical form of pre-eclampsia, a severe complication of the second half of pregnancy. However, this syndrome can occur in isolation in the absence of pre-eclampsia symptoms. Its pathophysiology remains still unclear. The clinical picture is often incomplete and fruste at first. To date, its diagnosis and management is still the subject of much controversy. Associated or not with a vascular and renal manifestations, the HELLP syndrome is a high-risk maternal disorder. The objective of this article is to review the pathophysiological and clinical data and current treatment.

Prevalence of hospital-acquired infection in a Tunisian hospital.

In order to estimate the prevalence of hospital-acquired infection (HAI) and research factors associated with its occurrence, a one-day prevalence survey was conducted at the Habib Bourguiba University Hospital, Tunisia. We studied 280 patients who had been present in the same ward for at least 48 h, and who had occupied a hospital bed between 17 April 2002 (midnight) and 18 April 2002 (midnight). The overall prevalence of HAI was 17.9%. The most frequently infected sites were the lungs (32%), surgical wounds (28%) and the urinary tract (20%). Microbiological documentation was available in only 28% of HAIs, and the most frequently isolated organisms were Gram-negative rods (80.8%). Results of multiple logistic regression analysis indicated that HAI is linked to the medical category, the use of intravascular devices and antibiotic prophylaxis. This survey provided information on the prevalence of HAI in Tunisian hospitals, the breakdown of infections, and HAI predisposing factors.

[Celiac disease, cerebral venous thrombosis and protein S deficiency, a fortuitous association?]. / Maladie coeliaque, thrombose veineuse cérébrale et déficit en protéine S, une association fortuite?

INTRODUCTION: Celiac disease is a pathology which is rarely associated with thrombosis complications. Cerebral vascular thrombosis has never been described in patients with a celiac disease. OBSERVATION: We report an observation of a 21-year-old girl with a history of celiac disease who was hospitalized in the intensive care unit for convulsive status epilepticus secondary to a cerebral venous thrombosis. The etiologic investigation of this thrombo-embolic complication revealed protein S deficit. Our patient improved under symptomatic treatment. COMMENT: This original observation confirms that celiac disease can be associated with cerebral venous thrombosis.

[Predictive value of pericatheter skin cultures in detecting catheter-related infections in a medical-surgical intensive care unit]. / Apport diagnostique de l'écouvillonnage de la zone d'insertion cutanée dans l'exploration des infections liées aux cathéters veineux centraux dans un service de réanimation médicochirurgicale.

OBJECTIVE: To evaluate the predictive value of pericatheter skin cultures in detecting catheter-related infections in critically-ill patients. STUDY DESIGN: Prospective study. PATIENTS AND METHODS: Over a 5 months period (from August 1(st) 2001 to December 31 2001), 500 patients were hospitalised, and 108 central venous catheters were prospectively examined. For each catheter, blood cultures, pericatheter skin cultures and semiquantitative culture of the catheter tip were performed. RESULTS: The median duration of catheterization was 8 days (interquartile: 8 days). Catheter was removed because of suspected infection in 54 cases (50%). Systemic catheter-related infection was found in 12 cases (11%) and the responsible organism was a gram-negative rod in 11 cases (92%). The negative predictive values of pericatheter skin cultures in the diagnosis of catheter-related infections and in case of suspected catheter-related infection were 89 and 86%, respectively. CONCLUSION: These results indicate that the pericatheter skin cultures are not an effective procedure for the conservative diagnosis of catheter-related infections and that the skin-insertion wound is not the major source of catheter-contamination in our unit.

[Post-trauma cerebral thrombophlebitis revealed by psychiatric disorders]. / Une thrombophlébite cérébrale post-traumatique révélée par des troubles psychiatriques.

Head injuries are described in the literature as a rare but possible etiology of cerebral venous thrombosis although no pathophysiological link has been identified. Trauma-related venous thrombi occurring in the brain produce a broad spectrum of clinical presentations. A purely psychiatric term is exceptional, leading to misinterpretation and late diagnosis. Positive diagnosis has been greatly improved by advances in magnetic resonance imaging with venous phase angiography, currently the gold standard exploration. We report the case of a patient who presented with post-trauma cerebral venous thrombosis revealed by psychiatric disorders.

[Cardiogenic pulmonary edema following ß2 agonist infusion for acute, severe asthma]. / Œdème aigu du poumon secondaire à l'administration intraveineuse de ß2 mimétiques pour asthme aigu grave.

We report the case of a severe acute pulmonary edema secondary to the administration of salbutamol to a patient admitted for severe asthma. The diagnosis of acute pulmonary edema was suspected on the clinical examination, chest radiography, biological (plasmatic Pro-BNP rate) and echocardiographic findings. Rapid improvement under dobutamine and mechanical ventilation argue in favour of cardiogenic pulmonary edema. The young age of our patient, the absence of history of cardiovascular disease and the chronology of this complication onset regarded to salbutamol infusion could suggest ß2 agonist involvement in this event. The improvement of cardiac function on echocardiography and the normal results obtained with myocardial perfusion scintigraphy performed 35 days later show the left ventricular reversible dysfunction.

[Crohn's disease with isolated vulvar localization and pregnancy. A case report]. / Maladie de Crohn à localisation vulvaire isolée et grossesse. A propos d'un cas.

Extra-intestinal manifestations of Crohn's disease are well described. A very uncommon gynaecologic manifestation of this disease is vulvar involvement. Till now, sixteen cases have been reported in the literature. We report a case of a pregnant woman with isolated vulvar involvement, without bowel manifestations. The diagnosis have been clinically uncertain, but the histopathology goes with Crohn's disease. Discussion point out the difficulties in diagnosis and management of this vulvar condition, and of its association with pregnancy.

[Uretero-uterine fistula: what is the role of ureteroscopy?]. / Fistule urétéro-utérine : quelle place à l'urétéroscopie ?

We present a case of uretero-uterine fistula that occurred following cesarean section complicated by postoperative peritonitis subsequent to failure of the uterine sutures. The distal and the proximal ends of the ureter were successfully explored by ureteroscopy. We discuss the contribution of ureteroscopy in ureter exploration and endoscopic treatment of uretero-uterine communications.

[Infralabyrinthine approach for cholesterol granuloma of the petrous apex]. / Granulomes à cholestérine de l'apex pétreux : intérêt du drainage par voie infra-labyrinthique.

Cholesterol granuloma of the petrous apex are cystic lesions, revealed by otologic and/or cranial nerve palsies, and diagnosed with the help of computed tomography and magnetic resonance imaging. Surgical treatment is not the complete removal of the lesion, but a conservative approach requiring drainage of the cyst and re-establishment of a correct aeration of the cavity. Three cases of cholesterol granuloma of the petrous apex were treated through a transmastoid infralabyrinthine procedure. Through a postauricular approach, a simple mastoidectomy was performed. The third portion of the facial nerve was identified. The posterior and lateral semicircular canals, and the jugular bulb were skeletonized. In two cases, a high diverticulum of the jugular bulb was impacted downwards with wax. The cystic lesion was then opened, and evacuated. The opening must be large to permit a correct aeration of the cavity and prevent stenosis of the drainage site. Hearing and the facial function were preserved in all cases. In conclusion, conservative approach to cholesterol granuloma of the petrous apex provides satisfactory drainage of this intrapetrous deep seated lesion with preservation of hearing and facial nerve function.