Aetiology of pneumonia following isolated closed head injury.

Patients undergoing mechanical ventilation (MV) after an isolated closed head injury (ICHI) have often been found to develop hospital-acquired pneumonia (HAP) well before subjects who require MV for different reasons. In a prospective study of patients receiving MV after an ICHI. 38 subjects (out of 65 with clinically suspected HAP) had a bacteriological diagnosis established on the basis of correspondence between cultures made from bronchoalveolar lavage and protected specimen brush (with quantitative thresholds of 10(4) and 10(3) cfu ml-1, respectively). Patients were separated according to the time of onset of HAP, with 20 subjects who developed HAP within 4 days of the start of MV (early onset pneumonia, EOP) and 18 subjects who developed HAP after the fourth day (late onset pneumonia, LOP). In those who had LOP, an expected spectrum of organisms was found, with Gram-negatives (especially Pseudomonas sp.) accounting for the majority of isolates. However, in EOP cases, Gram-positive bacteria (especially Staphylococcus sp. and Streptococcus pneumoniae) were found to largely predominate (P = 0.0000026). This confirms the high incidence of staphylococcal pneumonia in neurosurgery patients, and also provides evidence that the vast majority of such staphylococcal pneumonia are EOP. Unlike most previous reports, the microbiological findings from the present study suggest that a cut-off point of 4 days successfully distinguishes between EOP and LOP. Since these two clinical entities differ significantly in terms of pathogenesis and aetiology, preventive measures and therapeutical protocols have to be tailored accordingly.

Stability of cefodizime in solution and compatibility with other injectable drugs.

The stability of cefodizime in five intravenous infusion fluids (0.9% sodium chloride, 5% dextrose in water, 10% dextrose in water, 5% amino acid injection, 3% polygeline) was studied at room temperature and at 4 degrees C. The compatibility of cefodizime with commonly used injectable drugs (ranitidine, metoclopramide, folinic acid, furosemide, aminophilline, methylprednisolone, betamethasone, hydrocortisone, dexamethasone, ketoprofen, noramidopyrine, acetylcysteine, digoxin, diazepam, acetylsalicylic acid, chlorpromazine, clonidine, clomipramine) was studied in 0.9% sodium chloride and 5% dextrose at room temperature. At intervals during the storage periods (up to 24 hrs at room temperature; up to 6 days at 4 degrees C) color, clarity and solution pH were examined; cefodizime content was determined by a microbiological method. Cefodizime concentrations remained greater than 90% of the initial concentrations in all infusion fluids for at least 24 hrs at room temperature and 6 days at 4 degrees C. No visual changes or appreciable changes in pH were observed for any of the solutions. Immediate clouding was observed when chlorpromazine was combined with the solution of cefodizime. A color change was observed when acetylcysteine was mixed with cefodizime. An increase in pH was noted when aminophilline was added to the solution of cefodizime. However, cefodizime concentrations remained greater than 90% of the initial concentrations of the solutions after mixture with all the tested drugs for at least 24 hrs at room temperature.(ABSTRACT TRUNCATED AT 250 WORDS)

Fulminant hepatitis on withdrawal of chemotherapy in carriers of hepatitis C virus.

BACKGROUND: Fulminant hepatitis on withdrawal of chemotherapy has been described in chronic hepatitis B virus infection, but not in hepatitis C virus (HCV) infection. The relation between HCV and immune response to this virus, and disease severity, has not been examined. We present two patients with HCV who developed fulminant liver failure after chemotherapy was stopped. PATIENTS AND FINDINGS: Two patients with chronic HCV infection and malignant lymphoma received chemotherapy (cyclophosphamide, adriamycin, vincristine, bleomycin, etoposide, and prednisolone in patient 1; doxorubicin, bleomycin, vinblastine, and dacarbazine in patient 2), on withdrawal of which both developed fulminant hepatitis. Alanine aminotransferase (ALT) concentrations were greatly raised (6030 and 3870 IU/L in patients 1 and 2, respectively), and serum HCV-RNA was low in both patients when severe disease developed (10(2) genome equivalents per mL). Patient 1 died, and necropsy showed massive liver necrosis. INTERPRETATION: The findings suggest an immune-mediated mechanism for hepatocyte damage in HCV infection. Careful monitoring of ALT concentrations is necessary in such patients during and after chemotherapy.

Epstein-Barr virus as a trigger for autoimmune hepatitis in susceptible individuals.

During follow-up of healthy relatives of 13 patients with autoimmune hepatitis, seven cases of infectious mononucleosis due to Epstein-Barr virus (EBV) occurred. In two of these seven, before EBV infection, there was a defect in suppressor-inducer T lymphocytes specifically controlling immune responses to the asialoglycoprotein receptor, an antigen expressed on the hepatocyte surface. In these two, antibodies to this autoantigen persisted and increased after infectious mononucleosis, and autoimmune hepatitis developed within 4 months. In susceptible individuals, EBV is a trigger for autoimmune hepatitis.