Changes in glutathione-dependent redox status and mitochondrial energetic strategies are part of the adaptive response during the filamentation process in Candida albicans.

Candida albicans is an opportunist pathogen responsible for a large spectrum of infections, from superficial mycosis to systemic diseases called candidiasis. Its ability to grow in various morphological forms, such as unicellular budding yeast, filamentous pseudohyphae and hyphae, contributes to its survival in the diverse microenvironments it encounters in the host. During infection in vivo, C. albicans is faced with high levels of reactive oxygen species (ROS) generated by phagocytes, and the thiol-dependent redox status of the cells reflects their levels of oxidative stress. We investigated the role of glutathione during the transition between the yeast and hyphal forms of the pathogen, in relation to possible changes in mitochondrial bioenergetic pathways. Using various growth media and selective mutations affecting the filamentation process, we showed that C. albicans filamentation was always associated with a depletion of intracellular glutathione levels. Moreover, the induction of hypha formation resulted in general changes in thiol metabolism, including the oxidation of cell surface -SH groups and glutathione excretion. Metabolic adaptation involved tricarboxylic acid (TCA) cycle activation, acceleration of mitochondrial respiration and a redistribution of electron transfer pathways, with an increase in the contribution of the alternative oxidase and rotenone-insensitive dehydrogenase. Changes in redox status and apparent oxidative stress may be necessary to the shift to adaptive metabolic pathways, ensuring normal mitochondrial function and adenosine triphosphate (ATP) levels. The consumption of intracellular glutathione levels during the filamentation process may thus be the price paid by C. albicans for survival in the conditions encountered in the host.

[Respiratory complications of leptospirosis. Apropos of 6 cases, 3 of which show hemodynamic studies]. / Complications respiratoires des leptospiroses. A propos de 6 cas dont trois avec étude hémodynamique.

Six cases of leptospirosis with pulmonary complications are reported. Three cases were accompanying an hepato-nephritis due to L. icterohaemorrhagiae. The first patient died with massive hemoptysis. The second, presenting a bilateral pneumopathy predominant on the left side, recovered after plasma exchange and hemofiltration. The third case concerned a pulmonary edema complicating a vascular refilling in a shock syndrome it simply recovered. The three other cases were observed in an anicteric leptospirosis: in two cases, L. Australis was responsible; in the last, L. icterohaemorrhagiae was involved. The first patient had a radiologic picture simulating miliary tuberculosis. The second had pulmonary edema complicating a vascular refilling in a shock syndrome. The last was an acute respiratory distress syndrome, treated with artificial ventilation with penicillin therapy and corticotherapy. All these 3 patients recovered. The diagnostic, physiopathologic and therapeutic problems of these pulmonary complications of leptospirosis are discussed. The lesional nature of the pulmonary edema is proved by the low pulmonary wedge pressures observed with the Swan-Ganz Catheter.

[Unusual cause of digestive hemorrhage in chronic hemodialysis patients: splenic aneurysm with arteriovenous fistula]. / Une cause exceptionnelle d'hémorragies digestives chez l'hémodialysé chronique: l'anévrysme splénique, avec communication artério-veineuse.

A 45 years old woman, hemodialysed since 1981, with an history of Staphylococcal septicemia in may 1983, is admitted in emergency room in may 1984 for massive gastro intestinal bleeding. After oesogastro fibroscopy suspecting duodenal ulcer, because continuous and recurrent bleeding, a laparotomy find only symptoms of portal hypertension (ascites, venous dilatation on abdominal oesophagus and stomach). The ligation of this venous dilatations stop temporarily the gastro intestinal bleeding. But recurrence of this bleeding conduct to a celiac angiography discovering a splenic aneurysm with arterio venous fistula. The surgical treatment of this aneurysm can stop the gastro intestinal bleeding. Histopathologic observation of this aneurysm can suspect an infectious origin.

[Acute hyperkalemia disclosing an intraperitoneal rupture of an amebic liver abscess. Value of preoperative peritoneal dialysis]. / Hyperkaliémie aigue révélatrice d'une rupture intrapéritoneale d'abcès amibien du foie. Intérêt de la dialyse péritonéale pré-opératoire.

In a patient with shock and hyperkalemia , a peritoneal dialysis, started to treat an hyperkalemia , showed the presence of chocolate-like pus in the peritoneal cavity, and confirmed the intraperitoneal rupture of an amoebic liver abscess . Peritoneal dialysis led to the correction of the metabolic disorders and of the shock and restored the diuresis, ensuring favourable conditions to surgical intervention. Surgical drainage of the abscesses and ornidazole treatment led to complete recovery.

[Surgical approach to the so-called infectious perforations of the small intestine in Africa south of the Sahara (author's transl)]. / Attitude thérapeutique devant les perforations dites infectieuses de l'intestin grêle en Afrique noire.

Non traumatic perforations are frequent in Africa South of the Sahara and most often due to salmonellosis. From 50 cases recorded in Dakar, the authors study the main problems raised by diagnosis (specially in non reactive peritonitis requiring iterative controls), surgical tactic and procedure, and intensive care. In 86 p. 100 of the case they report on, the authors performed a suture completed by passive drainage. However, and in spite of the risk of leaking, resection had to be done either immediately or because suture failure. As patients were presented generaly in very bad condition, intensive cares were complex but essential. Death rate ranged between 25 p. 100 and 50 p. 100.

[Shock in abruptio placentae (author's transl)]. / L'état de choc au cours de l'hématome rétro-placentaire.

In sixty abruptions of the placenta observed during eighteen months, a severe condition of shock was observed in thirty per cent of patients. This shock state is seen during the abruption or after delivery. It's essentially a question of hemorrhagic shock, the importance of hemorrhagy being often underestimated, if the drop of blood pressure and blood losses are only estimated. The measurement of central venous pressure and the research of metabolic acidosis are better indexes of shock. This shock is associated with hypofibrinogenaemia and with other symptoms of disseminated intra-vascular coagulation. Fibrinolysis is rarely observed (3 times). Presence of fibrin degradation products is frequent. Renal complications are observed only in 1/6 of cases, but are frequently severe (one case of renal cortical necrosis). Heparinotherapy does not confirm the hope be suscited and seems to be a frequent source of ehmorrhagic complications in African women. Perfusion of fibrinogen, if useful, can be another source of complications. Rapid transfusion is the more effective treatment of abruption placenta and probably the less dangerous with strict control of the central venous pressure.

[Necrotizing amoebic colitis (a propos of 12 cases observed in Dakar)]. / Les amibiases coliques nécrosantes (à propos de 12 cas observés à Dakar).

Twelve cases of necrotizing amoebic colitis recorded in Dakar Hospital Principal are studied. The authors draw basis rules for an early surgical indication giving opportunity to detect not too extensive lesions and implement intensive care which may prove effective. Prognosis is still unfavourable with a death rate of two thirds.

[Shock during necrotic amoebic colitis (author's transl)]. / L'état de choc au cours de l'amibiase colique nécrosante.

Two varieties of conditions of shock may be isolated during necrotic amoebic colitis (13 cases). Eight patients present a simple hypovolemic shock secondary to wastage by diarrhea and perilesional oedema with globular, protein, alcaline and potassic deficiency. Its prognosis is relatively good, after vascular infilling and corrections of metabolic disorders. Five other patients present real toxi-infectious shock resulting from widespread tissue necrosis with auto-intoxication associated with septicemic complications. Its prognosis is frankly bad. The treatment is far more difficult. The use of cardiovascular analeptics, such as dopamine, after an infilling failure, is not always sufficient to re-establish the situation. The exeresis of necrotic tissues is an indispensable condition to remove the cause of the shock before septicaemic generalisation.