Efficacy of deoxycholate amphotericin B and unilamellar liposomal amphotericin B in prophylaxis of experimental Aspergillus fumigatus endocarditis.

OBJECTIVE: To evaluate and compare in vivo the protective efficacy of unilamellar liposomal amphotericin B (L-AmB) with that of deoxycholate amphotericin B (D-AmB) in experimental endocarditis. MATERIAL AND METHODS: In the rabbit model of experimental Aspergillus fumigatus endocarditis, two doses of each antifungal agent (1.5 mg/kg each) were administered intravenously at 4 hours and at 30 minutes before challenge with an inoculum of A. fumigatus. Three days later, the animals were sacrificed, and the aortic vegetations were analyzed. RESULTS: All 19 animals that did not receive chemoprophylaxis acquired endocarditis. In contrast, endocarditis developed in 2 of 10 animals pretreated with D-AmB (P < 0.01) and 3 of 8 animals pretreated with L-AmB (P < 0.01). Both D-AmB and L-AmB prevented the development of endocarditis due to A. fumigatus and decreased the concentration of fungi in the aortic vegetations by more than 1 log10. CONCLUSION: In the rabbit experimental model of Aspergillus endocarditis, D-AmB and L-AmB were equally effective in reducing the incidence of the infection and the tissue burden of fungi.

Globin chain synthesis in myelodysplastic syndromes.

Globin chain synthesis was studied in the reticulocytes of 30 patients with various myelodysplastic syndromes (MDS) to determine the alpha:beta globin chain synthetic ratio and its probable prognostic value. The mean (SD) value of the total alpha:beta ratio was 0.82 (0.45) ranging from 0.05 to 1.73. The same ratio in 10 normal controls was 1.01 (0.04). This difference was significant. Furthermore, the alpha:beta ratios were lower than normal in 14 patients (alpha-thalassaemia-like) (group I), almost within normal limits in 11 (group II), and higher than normal in five (beta-thalassaemia-like) (group III). In each group almost all the FAB subtypes were represented. The addition of exogenous haem in several of the test samples resulted in a slight to pronounced increase in the alpha:beta ratios, particularly in group I. In 92% of the high risk cases (refractory anaemia with excess blasts (RAEB), chronic myelomonocytic leukaemia (CMML] or 87.5% of patients who finally developed acute non-lyphoid leukaemia (ANLL) low or normal alpha:beta ratios were found. No significant correlation was noticed between alpha:beta ratios and various haematological variables or survival. It is concluded that in MDS the alpha:beta ratio varied enormously across the entire population of patients, as well as within each FAB subtype, thereby restricting its prognostic value. Although haem deficiency may be implicated in some cases of MDS, why this should be remains unclear.

Effect of isoniazid, a haem inhibitor, on globin chain synthesis in reticulocytes from non-thalassaemic and beta thalassaemic subjects.

The effect of isonicotinic acid hydrazide (INH), a potent haem inhibitor, on globin chain synthesis was studied in reticulocytes from the following groups of patients: four non-thalassaemic patients (group i); five beta thalassaemia heterozygotes (group ii); three Hb S/beta thalassaemia heterozygotes (group iii); and two additional patients--one with homozygous beta thalassaemia and the other with thalassaemia intermedia (group iv). This was done to determine whether haem inhibitors depress alpha globin chain synthesis. The progressive increase of INH concentration (10-40 mmol l-1) in reticulocytes from a beta thalassaemia heterozygote resulted in a remarkable decrease of the alpha and beta chain synthesis, ranging from 80% to 97% and from 74% to 96% of control values, respectively, and in a gradual drop of alpha:beta ratio from 1.87 to 1.38. Furthermore, in the samples incubated with 40 mmol l-1 INH, a pronounced inhibition of globin chain synthesis 77 (19%) for alpha chain and 67 (27%) for beta or beta S chain) and a substantial drop of the alpha:beta or beta S ratio in samples with INH (median 1.16) compared with that in samples without INH (median 1.70) were observed. The inhibitory effect of INH was significantly or completely corrected by adding exogenous haem. It is suggested that haem inhibition and the resulting preferential diminution of alpha chain synthesis could provide a new approach to the treatment of homozygous beta thalassaemia with an excess of detrimental free alpha chain in erythroid cells.

Comparative in vitro and in vivo efficacy of roxithromycin and erythromycin against a strain of methicillin-susceptible Staphylococcus epidermidis.

The in vitro and in vivo efficacy of roxithromycin was compared with that of erythromycin, against a methicillin-susceptible strain of Staphylococcus epidermidis. We performed standard in vitro testing (MIC, MBC, and time-kill kinetics) for roxithromycin, erythromycin, and rifampin. Both macrolides were bacteriostatic in vitro. There was no significant difference in microbial survival between erythromycin and roxithromycin groups in the time-kill kinetics (p = 0.3). For the in vivo experiments, using the rabbit experimental endocarditis model, roxithromycin was found to be inferior to erythromycin in decreasing the microbial burden of the endocardial vegetations (p < 0.05). Rifampin was highly effective, both in vitro and in vivo. In conclusion, the efficacy of roxithromycin was poor and inferior to erythromycin against a strain of methicillin-susceptible S. epidermidis.

Adverse effect of cis-diamminedichloroplatinum II (CDDP) on porphyrin metabolism in man.

The possible effect of cisplatin on porphyrin metabolism was studied in 25 patients with various malignancies treated with high-dose cis-diamminedichloroplatinum. Haematocrit, red blood cells, haemoglobin, white blood cells, platelets and reticulocytes together with coproporphyrin and protoporphyrin in red blood cells were determined before each course of chemotherapy in all patients. In addition, coproporphyrin, uroporphyrin, delta-aminolevulinic acid, and porphobilinogen were determined in the urine just before and 24 h after each course of treatment. Cisplatin administration was followed by a significant suppression of coproporphyrin and protoporphyrin in red blood cells and coproporphyrin, uroporphyrin, delta-aminolevulinic acid and porphobilinogen in urine. The changes observed paralleled similar changes in haematocrit, red blood cells and haemoglobin, strongly suggesting that cisplatin-induced anaemia may be due to a blocking effect of the drug affecting one or more enzymatic steps in the biosynthesis of porphyrins and haem. A moderate fall in the white blood cell count and a mild fall in platelets together with a steady increase of reticulocytes were also observed during treatment.

Pancreatic tuberculosis in non-immunocompromised patients: reports of two cases, and a literature review.

We present two cases of biopsy proven tuberculosis of the pancreas in non-immunocompromised patients diagnosed and treated in our unit within the last 14 years. The first case presented with abdominal pain and fever, and the second with iron deficiency anaemia and severe weight loss. In both cases abdominal ultrasound and computed tomography suggested a pancreatic carcinoma. There was no pulmonary or intestinal tuberculosis. The tuberculin skin test was positive. Upon exploratory laparotomy the macroscopic appearance of the pancreas was that of an inoperable pancreatic carcinoma. Following the histological diagnosis of pancreatic tuberculosis, both patients were successfully treated with triple antituberculous therapy for 6 months. Isolated pancreatic tuberculosis is an extremely rare disease with only 41 cases in non-immunocompromised patients reported worldwide (1966-1997). It is a curable disease and should be considered in the differential diagnosis of a pancreatic mass or abscess shown on ultrasound or computed tomography, especially in developing countries, where tuberculosis is common.

Paraplegia in a pregnant thalassemic woman due to extramedullary hematopoiesis: successful management with transfusions.

The investigation and treatment of a pregnant thalassemic woman who developed severe paraplegia is presented. Magnetic resonance imaging showed a paravertebral mass infiltrating the epidural space, resulting from extramedullary hematopoiesis (marrow heterotopia). The patient was treated successfully with repeated blood transfusions and made a complete recovery. The literature (36 cases) is reviewed and the magnetic resonance imaging features of spinal extramedullary hematopoiesis are presented. The efficacy of transfusions in the management of spinal cord compression due to marrow heterotopia in thalassemic patients is discussed.

Tuberculous esophagitis. Report of a case and review of modern approaches to diagnosis and treatment.

We describe a patient with tuberculous esophagitis who was referred to us with low-grade fever, but no esophageal symptoms. The diagnosis was established in biopsies obtained from a deep midesophageal ulcer seen on endoscopy. Investigation of the patient failed to identify any extra-esophageal tuberculous foci, but a computed tomography scan revealed mediastinal lymphadenopathy without lung involvement. Primary infection of the esophagus by tuberculosis is questioned, and widespread use of computed tomography may show it to be a fiction.

[Effect of starvation and phenobarbital on the activity of liver uroporphyrinogen synthetase]. / Effet du jeûne et du phénobarbital sur l'activité de l'uroporphyrinogène synthétase hépatique.

Liver uroporphyrinogen synthetase activity was measured in 45 mice, divided in three groups. The mice of the 1st group served as controls, those of the 2nd starved for 24 hours, while those of the 3rd were injected intraperitoneally with phenobarbital. The enzymic activity was found significantly (p less than 0.001) lower in the animals of the 2nd group (17.49 +/- 2.25 nmol/g/h) and higher in those of the 3rd (25.82 +/- 3.73 nmol/g/h) as compared to the controls (20.89 +/- 2.11 nmol/g/h). If these effects also exist in the human it could be suggested that starvation may be doubly harmful for the patients with acute intermittent porphyria by aggravating both their enzymic disorders. On the contrary, in the case of phenobarbital its undesired effect on porphyria may be moderated by a simultaneous induction of the uroporphyrinogen synthetase.

Intravenous fosfomycin for the treatment of nosocomial infections caused by carbapenem-resistant Klebsiella pneumoniae in critically ill patients: a prospective evaluation.

Intensive care unit (ICU)-acquired infections as a result of multidrug-resistant Gram-negative pathogens remain a serious problem in critically ill patients. Adult ICU patients who received intravenous fosfomycin were prospectively examined to assess its safety and effectiveness as an adjunct to the antimicrobial therapy of life-threatening infections caused by carbapenem-resistant Klebsiella pneumoniae. Fosfomycin was administered intravenously in 11 patients for treatment of hospital-acquired infections caused by carbapenem-resistant K. pneumoniae. Fosfomycin (2-4 g every 6 h) was administered in combination with other antibiotics. The mean +/- SD duration of treatment was 14 +/- 5.6 days. All patients had good bacteriological and clinical outcome of infection. All-cause hospital mortality was two out of 11 (18.2%) patients. No patient experienced adverse events related to the administration of fosfomycin. Intravenous fosfomycin may be a beneficial and safe adjunctive treatment in the management of life-threatening ICU-acquired infections caused by carbapenem-resistant K. pneumoniae.

Screening for thalassaemia and/or iron deficiency: evaluation of some discrimination functions.

The number concentration of erythrocytes in blood (RBC) and the discrimination functions MCV/RBC, (MCV)2 X MCH, DF = (MCV/fl) - (RBC/10(12).1(-1] - (8.1 X Hb mmol.1(-1] - 3.4 have been advocated as useful methods in screening programmes for thalassaemia. In the present work we attempted to estimate the value of each of these methods in screening programmes for thalassaemia and/or iron deficiency and in differentiating between these two conditions. One hundred and twenty-six subjects suffering either from iron deficiency anaemia or heterozygous beta, delta beta, 'silent' beta and alpha 1 thalassaemia were classified by using these methods. Forty healthy subjects served as controls. The RBC was greater than 5.5 X 10(12)1(-1) in 80% of the cases, the three discrimination functions were 'positive' in 91%, 94% and 92% respectively. MCV/RBC and (MCV)2 X MCH separated successfully the subjects with microcytic anaemia (heterozygous thalassaemia and iron deficiency) from normal controls. On the other hand the DF turned out to be more satisfactory than RBC in discriminating heterozygous thalassaemia from iron deficiency anaemia. Thus in population screening for thalassaemia either MCV/RBC or (MCV)2 X MCH ought to be used first and then the DF.

Imbalanced globin chain synthesis in heterozygous beta-thalassemic bone marrow.

Globin synthesis was studied in the bone marrow of seven heterozygous beta-thalassemic subjects. We found evidence of significant imbalance of alpha- and beta-chain production particularly at short times of incubation. There was a progressive decrease in alpha/beta-chain production ratio with increasing incubation time which was due to a decreased rate of net alpha-chain production, indicating that a large proportion of the newly synthesized alpha chains are degraded, particularly in bone marrow, within a few minutes of synthesis, leading to relatively low alpha/beta ratios if these are measured solely at incubation times greater than 10 min. The significant degradation of excess alpha chains explains why inclusion body formation and ineffective erythropoiesis, notable in beta-thalassemia homozygotes where there is gross chain imbalance, are not observed to any marked degree in heterozygotes.

Globin synthesis in normal human bone marrow.

Globin synthesis has been studied by in vitro labelling with radioactive amino acids in 60 normal human bone-marrow samples. Under the conditions routinely used to fractionate alpha and beta chains by chromatography alpha/beta production ratios ranging from 0.5 to 1.0 were obtained, depending on the method of sample treatment. This variation was due entirely to the presence of non-haem proteins derived from white cells which chromagraphy with globin on CM-cellulose. Purification of globin on Sephadex G100 and fractionation of alpha and beta globin chains by a modified chromatographic system resulted in alpha/beta ratios of unity. The relevance of these findings to the study of marrows in which there is unbalanced globin chain production is discussed.

Some parameters of haem synthesis in dialysed and non-dialysed uraemic patients.

Some parameters of haem synthesis were estimated in 60 uraemic patients (30 non-dialysed, 30 dialysed) and in 30 matched controls. Serum delta-aminolaevulinic acid and erythrocyte coproporphyrin and protoprophyrin were found significantly higher in the non-dialysed uraemics than in the controls. Erythrocyte delta-aminolaevulinic acid dehydrase (ALA-D) activity was 498 +/- 174 mumol/h.l in the non-dialysed patients, 321 +/- 146 in the dialysed (just before haemodialysis) and 833 +/- 281 in the healthy controls, the differences between these groups all being statistically significant (p less than 0.001). After haemodialysis the enzymic activity in the dialysed group increased significantly (380 +/- 167, p less than 0.001), but remained lower than normal (p less than 0.001). A similar pattern - although with less statistical significance of the differences between groups - was observed concerning erythrocyte uroporphyrinogen I synthase activity. Incubation of normal erythrocytes with uraemic plasma resulted in a considerable decrease of their ALA-D activity (from 830 +/- 263 to 616 +/- 126) while incubation of uraemic erythrocytes with normal plasma increased their ALA-D (from 384 +/- 139 to 494 +/- 77). Addition of zinc in the haemolysate caused a similar induction of ALA-D in both controls and uraemics. The zinc-induced uraemic ALA-D practically reached normal levels. The mechanism of enzymic depression and the possible role of elevated delta-aminolaevulinic acid concentrations (to which depressed ALA-D activity considerably contributes) in the pathogenesis of the neurologic manifestations of uraemia, are discussed.

Rapid proteolysis of puromycyl peptides in non-thalassaemic and thalassaemic erythroid cells.

The proteolytic degradation of labelled pyromycyl polypeptides was investigated in human intact erythroid cells derived from the bone marrow of eight non-thalassaemic patients and the peripheral blood of eleven thalassaemics (eight splenectomized beta thalassaemia heterozygotes and three sickle-cell beta thalassaemics). These abnormal polypeptides are rapidly degraded to soluble trichloroacetic-acid (TCA) fragments with a half-life of 12 min both in bone marrow and peripheral blood. This comes very close to the half-life reported for the puromycyl peptide degradative system in rabbit reticulocytes (15 min). The relationship of the present proteolytic system to the ATP-dependent one, described in rabbit reticulocytes, and to that responsible for the free alpha-chain degradation in beta thalassaemia is discussed.

Dissociation of ACTH, beta-endorphin and cortisol in graded sepsis.

The function of the hypothalamic-pituitary-adrenal axis as related to the degree of severity of a septic process was assessed by measuring plasma levels of beta-endorphin, ACTH and cortisol. Sixty-one cases of postoperative patients treated at the intensive care unit were classified into four groups according to the severity of infection: Group 1 (control) included patients who did not show any sign of infection, group 2 patients with sepsis, group 3 patients with septic syndrome and group 4 patients with septic shock. Compared to G1 patients' ACTH values (4.16+/-2.6pg/ml), a statistically significant increase in ACTH values in various stages of septicemia (p < 0.005) with a noticeable difference also between G3 (7.11 +/-3.7pg/ml) and G4 (11.5+/-6.6pg/ml) (p<0.05) was found. Differences were also observed in beta-endorphin (with a level of significance between the several groups of p = 0.0001). Also, beta-endorphin values in G4 (40.6+/-30.3 pg/ml) differed significantly from each of G1 (17.5 +/-6.6 pg/ml), G2 (21.1+/-11.3 pg/ml) and G3 (23.5+/-12 pg/ ml) (p<0.05). A progressive hypercortisolemia was obvious, with values of G4 (37.2+/-15.6 microg/dl) differing significantly from those of G1 (18+/-4.6microg/dl) and G2 (24-/+8.4microg/dl) (p<0.05) and of G3 (28.5+/-12.3 microg/dl) from that of G1 (p < 0.05). Interestingly, a dissociation of ACTH, beta-endorphin and cortisol was observed, in that the increased values of beta-endorphin and cortisol, detected in the G3 were not associated with a parallel increase in ACTH. These findings might be interpreted in the sense of an impairment of the stress stimulation of the hypothalamic pituitary adrenal axis. Provided that such a situation can be lethal, our results further confirm the idea that a low-dose, steroid replacement might be beneficial to critical illness.

Antiphospholipid syndrome: clinical and therapeutic aspects.

The purpose of the present study was to evaluate patients with the antiphospholipid syndrome with particular attention to their initial clinical features, final diagnoses and the course of thrombotic events in association with therapy. The methodology applied was the following: retrospective analysis of 30 patient files (20 female, 10 male) with antiphospholipid syndrome (APS). Four types of therapy were evaluated for their efficacy to prevent thrombotic recurrences, aspirin 100 mg daily plus low-dose prednisone 10-15 mg daily, warfarin (with international normalized ratio 2 to 2.6), immunotherapy alone and no therapy. None of the patients was followed-up during pregnancy. The probability of thrombosis-free survival was estimated according to Kaplan-Meier method, while the statistical significance was tested by the log rank test. There were 21 patients with primary APS and 9 with secondary, 8 of whom had SLE and one patient who had primary Sjögren's syndrome. The age at onset and the disease duration did not differ between men and women, while patients with secondary APS had a longer disease duration than patients with primary APS, a finding indicating that SLE patients develop, for unknown reasons, APS a long time after the initiation of their disease. Twenty patients experienced recurrent thrombotic events (a total of 46 recurrences) of which 43 (93%) were identical to the first event. Thus, in the majority of the cases arterial were followed by arterial and venous by venous thrombotic events: a finding suggesting a tissue-related factor for initiation of thromboses.(ABSTRACT TRUNCATED AT 250 WORDS)

delta-Aminolaevulinic acid dehydratase as an index of lead toxicity. Time for a reappraisal?

delta-Aminolaevulinic acid dehydratase activity is traditionally accepted as the most sensitive measurable biological index of lead toxicity. We have measured delta-aminolaevulinic acid dehydratase activity and blood lead concentration in 47 healthy controls (A), 42 iron deficient patients (B) and 38 occupationally exposed to lead subjects (C). Blood lead levels [mean (SD)] did not differ between groups A and B [0.51 (0.21) and 0.43 (0.19) mumol L-1, respectively] while those of group C [2.28 (0.56) mumol L-1 were significantly higher (P < 0.001) as compared to the controls. delta-Aminolaevulinic acid dehydratase activity [mean (SD)] was significantly increased [3599 (1909) mumol L-1 h-1] in group B and decreased in group C [1052 (532) mumol L-1 h-1] as compared to the controls [2034 (446) mumol L-1 h-1] (P < 0.001). There was a significantly negative correlation of logarithm of delta-aminolaevulinic acid dehydratase with lead in both groups B (P < 0.05) and C (P < 0.001) but not in group A (P = 0.1). delta-Aminolaevulinic acid dehydratase activity had a high specificity (100%) but a low sensitivity (37%) as an index of toxic lead exposure. According to our data the value of delta-aminolaevulinic acid dehydratase measurement in the diagnosis of lead intoxication is doubtful in cases with low blood lead levels, while in the presence of iron deficiency its reliability is further reduced, since low blood lead levels may be falsely predicted. delta-Aminolaevulinic acid dehydratase activity should be restricted only to monitoring cases with moderate or severe lead poisoning.

A new approach to the diagnosis of beta-thalassaemia.

By use of isoelectric focusing in polyacrylamide gel rods we were able to detect traces of HbA (approx. 1%) as a sharp and discrete band. By overloading the gel considerable amounts of HbA (slightly contaminated with HbF) could be detected and isolated. The focused HbA was retrieved from the gels, separated from the carrier-ampholytes and concentrated by a one-step electrophoresis technique. With 3H-leuci ne-labelled haemolysates, after globin chain separation on CM-cellulose, an increase of the beta-chain counts relative to gamma-chain counts was obtained. The study of two cases of high HbF homozygous beta-thalassaemia has demonstrated that this technique may be a valuable tool in detecting minute amounts of HbA mainly in high HbF beta-thalassaemias.

Erythrocyte delta-aminolaevulinic acid dehydratase, urinary porphyrins and porphyrin precursors in iron deficiency anaemia.

In 20 iron deficient patients and 21 normal controls the activity of the enzyme delta-ALA dehydratase of erythrocytes was assayed. In addition the urine porphyrins and porphyrin precursor excretions were measured. It was found that in sideropenic patients the erythrocyte delta-ALA dehydratase activity was almost constantly higher than in normals; the difference of the mean values being statistically significant (p less than 0.005). A significant diminution of delta-ALA (p less than 0.0025) urine excretion was observed, whereas the urine excretion of PBG, CP and UP was found within the normal limits. The results are compared to those reported by other authors.