Gram-positive infections in granulocytopenic patients: an important issue?

Gram-positive pathogens have become a common cause of bacteraemia in granulocytopenic cancer patients. This has been partially attributed to the use of central intravenous devices such as Hickman catheters; mucositis secondary to intensive antineoplastic chemotherapy or herpes infections may also be the source, especially for streptococci, whereas the skin is most probably the source for Staphylococcus epidermidis. Antimicrobial prophylaxis recommended mainly with the aim of reducing the incidence of Gram-negative bacillary infections may also play a significant role. The rate of response of documented infections caused by Gram-positive cocci to 'standard' empirical therapy (which has been mainly directed against Gram-negative bacilli) has been unsatisfactory although the lethality reported has been low. These results raise an important question, whether or not a specific anti-Gram-positive antibiotic such as vancomycin, should be added to the empirical regimen. A recent study suggested that empirical vancomycin provided no benefit since the mortality due to Gram-positive infections was low and a favourable outcome was obtained by adding a specific antibiotic after bacteriological documentation. However, others have shown that empirical use of vancomycin was associated with a more rapid resolution of fever. Vancomycin has been associated with an excess rate of side-effects and is difficult to administer. Another important question is whether or not antimicrobial prophylaxis for gut decontamination should include anti-Gram-positive cover. Recent studies have confirmed that Gram-negative bacillary bacteraemia may be prevented by oral gut decontamination but not bacteraemia due to Gram-positive bacteria.(ABSTRACT TRUNCATED AT 250 WORDS)

Aspects of infections in children with cancer

There are some differences between pediatric and adult cancer patients in terms of the problem of infection but it is doubtful whether such discrepancies justify different therapeutic approaches. For example, according to the results of EORTC trial IV, children seem to show lower overall (3% vs 19%) and infectious (2% vs 8%) mortality than adults, probably due to differences in underlying diseases and to a basic better physical integrity. Central intravenous catheters appear to be indispensable in the modern management of neoplastic diseases, especially in pediatric oncology. A prospective study performed in our institution on 157 Broviac catheters, has shown: 1. Of all microbiologically documented infections, occurring in children undergoing cancer chemotherapy and radiotherapy, 27% are related to the catheter 2. Gram-positive cocci are the leading pathogens (78%) of such infections 3. Catheter-related infections often occur in non-neutropenic patients 4. Such infections can be successfully treated without removing the intravenous device. The experience of the EORTC Cooperative Group and of other centers throughout the world shows that gram-positive cocci are increasingly being isolated as the cause of infections in cancer patients. This phenomenon is probably multifactorial in origin and appears to be more evident in pediatrics. For example, in our institution, during the last 5 years gram-positive organisms have caused 69% of all bacteremias. Moreover, these organisms, while responding poorly to the presently used empirical antibiotic regimens, seem not to be as aggressive as gram-negative organisms and cause lower mortality. There is therefore controversy over whether or not to include anti-gram-positive coverage in early empirical regimens. In our institution, a pilot study comparing ceftazidime + amikacin (C + A) and ceftazidime + vancomycin (C + V) seems to show an overall advantage for C + V. This advantage, however, is not statistically significant. One finding to be pointed out is that five of ten staphylococcal infections failed to respond to C + V and that in these cases a third antibiotic had to be added. Therefore, it is likely that, at least in institutions in which methicillin-resistant staphylococci are prevalent, a triple antibiotic empirical regimen will provide the best coverage, but this can result in overtreatment. However, only prospective, randomized and multicenter trials will be able to answer such questions definitely.

[Autologous bone marrow transplantation in children. Use of parenteral nutrition]

Children undergoing ABMT, a procedure which entails massive doses of chemotherapy along with total-body irradiation, are candidate to develop severe gastrointestinal toxicity and prolonged anorexia requiring administration of Parenteral Nutrition (PN) for variable periods. We report a series of 35 consecutive children affected by malignancies who underwent 37 courses of PN after ablative therapy followed by ABMT. Age ranged from 8 months to 17 years; 16 were females, 19 males. There were 23 cases of neuroblastoma, 5 of Wilms' tumor, 3 of acute myelogenous leukemia, 2 of Ewing's sarcoma, 1 case each of rhabdomyosarcoma and acute lymphoblastic leukemia. All patients developed severe neutropenia for 9-42 days (median 18 d). Fever occurred in all patients; sepsis was documented in 10. Duration of PN ranged from 10 to 64 days (23 +/- 9; mean +/- SD). PN solution, containing crystalline L-Aminoacids (8.5%) mixed with 33% glucose, minerals, trace elements and vitamins provided for children a caloric intake of 49.8 +/- 17.3 Kcal/Kg/day with a nitrogen intake of 0.26 +/- 0.27 g/Kg/day. Nutritional assessment, utilizing percent ideal body weight, serum protein electrophoresis, C3, pseudocholinesterase and fibrinogen, was performed at the beginning and at the completion of each course of PN. Mean percent ideal body weight was 95.8 before PN, 98.5 on last day of PN (p less than 0.0005). Other parameters did not change significantly. No metabolic complication nor severe electrolyte imbalance were observed except for 5 patients who developed hypokalemia in coincidence with administration of Amphotericin B.(ABSTRACT TRUNCATED AT 250 WORDS)

Emerging microorganisms in cystic fibrosis

Pseudomonas aeruginosa is the most common bacterial isolate obtained from patients with cystic fibrosis of the lungs. Recently, however, new multiresistant organisms have emerged, whose identification may be difficult and whose pathogenic role proves hard to define. Of the 71 strains isolated from 24 patients with cystic fibrosis during acute flareups of pulmonary symptoms, 48 turned out to be Pseudomonas aeruginosa (67.6%); 11 were Pseudomonas non-aeruginosa (15.5%); and 12 were Achromobacter xylosoxidans (16.9%). Each bacterial isolate was tested for sensitivity to nine antibiotics (ceftazidime, azlocillin, piperacillin, aztreonam, cefsulodin, cefoperazone, amikacin, tobramycin, and sisomycin) in terms of minimum inhibitory concentration and minimum bactericidal concentration values. In this series, Achromobacter xylosoxidans proved the species least responsive to treatment, and ceftazidime the most active antibiotic both against Achromobacter and against strains of the genus Pseudomonas. Twenty-three different associations of ceftazidime with aminoglycosides, tested for activity on the multiresistant strains, failed to show synergism of action.

[Total body irradiation, vincristine in continuous infusion and high-dose melphalan with transplant of autologous bone marrow in the treatment of neuroblastoma]

High dose chemo-radiotherapy followed by autologous bone marrow transplantation (ABMT) is known to be an effective treatment in stage IV neuroblastoma (NB). Since October '84, 19 children with NB (12 relapsed or resistant: Group A; 7 in first CR: Group B) received ablative therapy (AT) consisting of VCR (4 mg/mg), L-PAM (140 mg/mg) and fractionated TBI (1000 Rads). Induction strategy at diagnosis or at relapse included high dose Peptichemio, 2-3 cycles of Vincristine-Cyclophosphamide--high dose Platinum and surgery. Bone marrow was harvested after 2 evaluation proved negative by cytomorphology, histology and immunofluorescence. Mononuclear cells (median 6.7 x 10(7)/kg) were cryopreserved and reinfused without purging. At the time of AT in Group A8 children were in CR, 4 had minimal diseases; in Group B 6 were in CR and one in PR. One toxicity-related death occurred on day 7 in a child in first CR; median duration of granulocytopenia 0.5 x 10(9)/l and thrombocytopenia less than 50 x 10(9)/l were 20 days (R: 9-40) and 27 days (R: 11-51) respectively. Persistent immune thrombocytopenia occurred in 4 children. Fever higher tha 38 degrees C developed in all patients: sepsis was documented in 6 patients. Extramedullary toxicity was moderate: GI tract was the most affected. Two out of 5 children who received AT having residual disease achieved CR; relapse or progression of disease occurred in all these patients. Four out of 8 children in second or subsequent CR and 4 out of 5 in first CR are alive and well at 3-12 months (median 7).(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of ceftazidime in the treatment of 80 infectious episodes in compromised children

The efficacy of ceftazidime in the treatment of infections in compromised children was evaluated in 80 such episodes occurring in 64 patients with various underlying diseases. Among the patients treated, 9 were newborns with severe neonatal distress, 21 were children with cancer and neutropenia, 8 were surgical patients, 22 had cystic fibrosis and 4 were suffering from meningitis. The following types of infections were treated: 19 bacteriologically documented and 8 possible septicemias (the latter only in newborns and neutropenic cancer patients); 2 severe upper respiratory tract infections in cancer patients; 8 soft tissue or skin infections; 1 cholangitis; 1 pneumonia; 1 osteomyelitis; 1 mediastinitis; 35 infectious exacerbations of underlying pulmonary disease in cystic fibrosis patients; and 4 meningitides. In almost all cases ceftazidime was administered intravenously in combination with an aminoglycoside. In 2 cases it was also given intrathecally or intraventricularly. Bacteriological documentation was achieved in 70 out of 80 episodes. A successful outcome was obtained in 79% of the cases with slight and statistically nonsignificant differences between groups of patients with different etiological patterns in terms of prevalence of gram-positive microorganisms. Tolerance of the treatment was uniformly good, only one patient showing a mild, transient transaminase elevation.

[Advantages of a permanent venous access in children treated for cancer. Preliminary results]

Current therapy for children with cancer includes a variety of invasive procedures many of which require repeated venous access over a considerable period of time. Such procedures are poorly tolerated by children and by their veins. Recently it has become possible to undertake the majority of such procedures by means of permanent indwelling silastic catheters improving the quality of life of the children and their parents and increasing the scope of therapeutic intervention. In the period July '83 - August '84 we have used 46 of these catheters in 45 children with malignant disease, 12 with acute myeloid leukaemia, 12 with neuroblastoma, 7 with B cell leukaemia-lymphoma, 6 with rhabdomyosarcomas, 2 with Ewing's Sarcoma, 2 with Wilms' tumor and 1 case each of Hodgkin's disease, teratocarcinoma, osteosarcoma and juvenile chronic myeloid leukaemia. The children's ages ranged from 2 months to 14 years; 22 were male and 23 female. The catheters were inserted under general anaesthesia (duration 20-40 minutes) usually without difficulty, except for a single patient in whom no suitable vein could be found. No complications connected with the placement of the catheter were observed. Subsequent management of the catheter was initially complicated and time-consuming, but was subsequently simplified so that acceptance by parents, children and nursing staff was eventually excellent. The duration of use of 46 catheters ranges from 7 to 350+ days; 24 catheters are presently in use at 30-350+ days from insertion. Eight children died as a result of disease progression and two of sepsis with the catheter in place.(ABSTRACT TRUNCATED AT 250 WORDS)

[Hereditary fructose intolerance]

Two cases of hereditary fructose intolerance are reported. In the first one the symtomatology has started with an acute hepatic failure; the second one has come to our observation with a diagnosis of intrahepatic biliary duct atresia. It is underlined the difficulty of a differential diagnosis, in infants with serious hepatic failure, between infectious, metabolic and others illnesses.

[Congenital hepatic fibrosis]

According to their experience and to a review of the most important papers in the field, the Authors examine the clinical, morphological, diagnostical and therapeutical aspects of congenital hepatic fibrosis. The initial sign is almost always hepatosplenomegaly and diagnosis can be achieved by means of clinical, anamnestic, histological and ecotomographic findings. Relationships among congenital hepatic fibrosis, infantile polycystic disease of the kidney and liver and Caroli's disease are stressed.

[Progress in cerebrospinal fluid diagnostic studies contributed by cytocentrifugation]

Immunological studies in cerebrospinal fluid of acute viral and tubercular meningitidis, and other inflammatory diseases of CNS require a strict cellular detection and identification, that may be reached by cytocentrifugation. Several cases are reported, in which cytocentrifugation was obtained by Shandon-Elliott cytocentrifuge. Some morphological aspects are discussed, as the presence of high levels of "reticulomonocytes" in encephalitis, plasma-cells in acute disorders, activated lymphocytes in viral meningitis.