[Necrotic skin lesions caused by pet rats in two teenagers]

We report 2 observations in young girls who, after exposure to domestic rats from the same pet shop, presented with inflammatory and necrotic skin wounds in the neck and face. Since lesions did not improve with antibiotic therapy, surgical excision of necrosis healed the wounds, with a 2nd intervention necessary in 1 patient. All bacteriological investigations appeared to be negative; finally, electron microscopy of excised subepidermal tissue and PCR characterization provided the diagnosis of cowpox virus (CPXV) infection. CPXV is part of the Orthopox virus genus, like variola virus, and is generally transmitted to humans by infected cats or rodents. CPXV infection should be kept in mind when macular, vesicular, or necrotic cutaneous wounds do not improve with antibiotics.

Cowpox virus transmission from pet rats to humans, France

In early 2009, four human cases of cowpox virus cutaneous infection in northern France, resulting from direct contact with infected pet rats (Rattus norvegicus), were studied. Pet rats, originating from the same pet store, were shown to be infected by a unique virus strain. Infection was then transmitted to humans who purchased or had contact with pet rats.

Discitis due to Clostridium perfringens

INTRODUCTION

A combination of disk space narrowing and vacuum phenomenon on radiographs of the spine is usually considered a reliable indicator of degenerative disk disease. We report a case in which vacuum phenomenon was related to Clostridium perfringens discitis.

METHODS

A 79-year-old woman was admitted for inflammatory low back pain that had worsened steadily over the last 2 months. Her body temperature was normal, laboratory tests showed inflammation (erythrocyte sedimentation rate, 61 mm/h; and C-reactive protein, 13 mg/L), and blood cultures were negative. Imaging studies (radiographs, computed tomography [CT], and magnetic resonance imaging) indicated L4-L5 discitis. Vacuum phenomenon within the L4-L5 disk was seen on radiographs and CT scans. C. perfringens was recovered by fine-needle biopsy of the disk. Diverticular disease of the colon was the only identifiable portal of entry. Amoxicillin therapy ensured a full recovery.

DISCUSSION

C. perfringens discitis is rare, with only 7 published cases in humans. A gastrointestinal portal of entry was identified in 70% of cases. Radiographs or CT scans visualized vacuum phenomenon in 80% of cases. Positive blood cultures were noted in 75% of cases. The outcome was favorable with antibiotic therapy, even when a single-drug was used. The other characteristics of C. perfringens discitis were indistinguishable from those of discitis caused by the usual organisms.

CONCLUSION

Presence of gas within the disk does not rule out infectious discitis and may indicate C. perfringens discitis.

[Therapeutic principles of staphylococcal infections--Role and limitations of standard compounds]

Antibiotic therapy plays an important (but not exclusive) role in the treatment of staphylococcal infections. Measures aimed at reducing the bacterial inoculum through local procedures must be envisaged as often as possible. The removal of any foreign, infected materials is essential to success. In this article, we review the different, active antibiotics available, their advantages and disadvantages and their indications. In the light of these data, we propose a therapeutic approach to severe bacterial infection caused by a cluster of Gram-positive cocci. Staphylococcal infections pose daily therapeutic problems, whether in open-care practice or intensive care units. The specificity of staphylococcal infections encountered in an intensive care setting require a therapeutic approach which takes account of the context, and particularly of the incidence of resistant staphylococcal infections.

Delayed admission for ethylene glycol poisoning: lack of elevated serum osmol gap

In the absence of an immediately available serum ethylene glycol (EG) assay, the diagnosis of EG poisoning is usually based on anamnesis, clinical findings and presence of metabolic acidosis with elevated serum anion gap, elevated serum osmol gap, hypocalcemia and crystalluria. We report two cases of EG poisoning, both presenting without an elevated serum osmol gap and we discuss conditions which facilitate such a presentation, especially delayed hospital admission. Finally, we confirm the fact that determination of the osmol gap can fail as a screen for EG poisoning.

Iatrogenic diseases as a reason for admission to the intensive care unit: incidence, causes, and consequences

BACKGROUND

Data on iatrogenic diseases (IDs) have been recorded for the past 25 years. We determined whether aging of the general population and medical advances, including more powerful drugs and complex procedures, have altered the incidence, causes, and consequences of severe IDs during this period.

METHODS

One-year retrospective study was conducted in an adult medical-surgical intensive care unit (ICU) affiliated with a French general hospital in an area of 200 000 inhabitants. All the patients admitted to the ICU during 1994 were screened for IDs. Patients with community or hospital-acquired IDs on admission were included. Follow-up assessed morbidity, mortality, workload, and costs of care for IDs, and the rate of preventable IDs. were included; the cause of the ID was drugs in 41, medical acts in 12, and surgical acts in 15. These 68 patients were in the ICU for 472 days, with a 13% fatality rate (9 patients) and a financial cost of US $688 470. They were not different from the 555 other ICU patients in terms of severity, mortality, workload, and length of stay in the ICU. Risk factors for ID were old age and the number of prescribed drugs. The rate of preventable ID was 51%.

CONCLUSIONS

Iatrogenic diseases are a persistent and important reason for admission to the ICU, and the risk factors, causes, and consequences remain unchanged since 1980. Despite 25 years of experience with high-technology medicine, ID still has a negative impact on the health and resources of society.

[Coronary gas embolism after laparoscopic surgery]

Gas embolism is a severe complication of laparoscopic surgery. We report two cases: one with lethal peroperative cardiac arrest from massive coronary artery gas embolism recognized during open-chest cardiac massage; the second case, also associated with coronary artery gas embolism, resulted in severe but transient abnormal left ventricular anterior wall motion, subepicardial ischaemia and injury in ECG leads V1 to V5, but unremarkable coronary arteriography and full recovery. The pathophysiology of gas embolism occurring during a laparoscopic procedure, the mechanisms of gas entry into the systemic vascular bed, the clinical, ECG, pulse oximetry, end-tidal CO2 concentration changes and alarm signs are discussed. The diagnostic value of Doppler transoesophageal echocardiography when possible is underlined, and emergency management of gas embolism is considered.

[Patients admitted to the intensive care unit for iatrogenic disease. Risk factors and consequences]

PURPOSE

Data pertaining to iatrogenic diseases have been recorded over the last 25 years. Regarding the evolution of medical practice (general ageing, more and more powerful drugs and complex procedures), it is not known whether the incidence and the consequences of iatrogenic diseases have changed since their first evaluation.

METHODS

To determine the admission rate to intensive care units for iatrogenic diseases, with the purpose of analyzing risk factors and consequences, and to compare our results with previous data recorded in 1979 (admission rate: 12.6%, mortality: 20%, preventable events: 47%), a 1-year retrospective study was conducted in an intensive care unit (ICU).

RESULTS

During 1994, 68 (10.9%) out of 623 patients were admitted to the ICU for iatrogenic diseases (drugs: 41, medical acts: 12, surgical acts: 15). They were not different--in terms of severity, mortality, workload and length of stay in the ICU--from the other 555 patients hospitalized for other reasons. They were hospitalized on average for 472 days in the ICU, with a 13% fatality rate and a financial cost of US $688,470. Risk factors for iatrogenic diseases were the age and the number of prescribed drugs. The rate of preventable events was 51%.

CONCLUSIONS

In this study, the occurrence of life-threatening iatrogenic diseases was a persistent and important purpose for admission to the ICU. Risk factors and consequences are still identical to those reported in 1979. Our results emphasize the persistence of the noxious impact of iatrogenic diseases on the quality and cost of medical care.

Clinical and bacteriologic survey of epidural analgesia in patients in the intensive care unit

BACKGROUND

The risk of bacterial contamination related to epidural analgesia in patients cared for in the intensive care unit has not been assessed. Thus the authors studied patients who received care in the intensive care unit who were given epidural analgesia for more than 48 h to determine the rates of local, epidural catheter, and spinal space infection and to identify risk factors.

METHODS

Each patient receiving epidural analgesia for longer than 48 h was examined daily for local and general signs of infection. A swab sample for culture was taken if there was local discharge; all epidural catheters were cultured on withdrawal. All patients underwent weekly neurologic monitoring for 1 month; those with positive epidural catheter cultures had one spinal magnetic resonance image scan.

RESULTS

The 75 patients cared for in the intensive care unit who were studied had been receiving epidural analgesia for a median of 4 days (interquartile range, 3.5 to 5 days). Twenty-seven patients had signs of local inflammation (erythema or local discharge), and nine of these had infections. All the patients who had both local signs also had infection. All nine infections were local (12%), but four patients also had epidural catheter infections (5.3%). No patient with erythema alone or without local signs had a positive epidural catheter culture. No spinal space infection was diagnosed. Staphylococcus epidermidis was the most frequently cultured microorganism. Local infection was treated by removing the epidural catheter without any antibiotics. Concomitant infection at other sites (21 of 75 patients, or 28%), antibiotic therapy (64 of 75 patients, or 85%), the duration of epidural analgesia, and the insertion site level of the epidural catheter were not identified as risk factors for epidural analgesia-related infections.

CONCLUSIONS

The risk of epidural analgesia-related infection in patients in the intensive care unit seems to be low. The presence of two local signs of inflammation is a strong predictor of local and epidural catheter infection.

Mortality due to ventilator-associated pneumonia or colonization with Pseudomonas or Acinetobacter species: assessment by quantitative culture of samples obtained by a protected specimen brush

Ventilator-associated pneumonia (VAP) due to multiresistant pathogens is associated with a high death rate. We analyzed the relationship between VAP due to Pseudomonas or Acinetobacter species and death by comparing the outcomes for patients colonized with these pathogens (bacterial counts of < 10(3) cfu/mL) with those for patients with pneumonia due to these pathogens (bacterial counts of > or = 10(3) cfu/mL). Samples were obtained systematically with a protected specimen brush when pneumonia was suspected. Clinical characteristics at admission to our intensive care unit and clinical features at the time of suspicion of VAP were not significantly different between colonized patients and those with VAP. Mortality rates were 29% among colonized patients and 73% among patients with VAP (P < .001). These results demonstrate a relationship between a high mortality rate and the development of pneumonia due to multiresistant, nonfermenting, gram-negative bacilli ( > or = 10(3) cfu/mL) in the lower airways of patients receiving ventilatory support.

Teicoplanin: a well-tolerated and easily administered alternative to vancomycin for gram-positive infections in intensive care patients

A prospective, randomized multicentre study was conducted in order to evaluate the potentially superior tolerability profile of teicoplanin plus netilmicin compared with vancomycin plus netilmicin in patients in ICUs. We considered that these glycopeptides have been shown to have comparable efficacy and that comparative tolerability is of paramount importance, particularly in severely ill patients. A total of 56 patients were enrolled into the study (36 males and 20 females). Twenty-four patients were included in the teicoplanin plus netilmicin group (15 males, 9 females: mean age 56.8 years). The mean simplified acute physiological score (SAPS) was 9.4 (range 4-20). Thirty-two patients were randomized to receive vancomycin plus netilmicin (21 males, 11 females; mean age 56.4 years). The mean SAPS was 9.3 (range 2-16). Septicaemia was the most common infection (14 cases in each group). Most infections were caused by Staphylococcus aureus or coagulase-negative staphylococci. The mean daily doses were: for teicoplanin, 457 mg (6.7 mg/kg); for vancomycin, 1678 mg (24.4 mg/kg); and for netilmicin 263.3 mg (3.9 mg/kg) in the teicoplanin group and 248 mg (3.8 mg/kg) in the vancomycin group. The trough levels of teicoplanin in the serum remained mostly between 7 and 10 mg/l, while more fluctuation was seen in patients receiving vancomycin. The mean trough levels of netilmicin in the serum were 1.2 (SD 0.9) mg/l in the teicoplanin group, compared with 1.7 (SD 1.4) mg/l in the vancomycin group (NS: p > 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

A non-comparative study of the efficacy and tolerance of cefepime in combination with amikacin in the treatment of severe infections in patients in intensive care

Patients in intensive care units (ICUs) are at increased risk of developing nosocomial infections. This is of special concern in the immunocompromised patient, particularly with regard to multiresistant pathogens. We evaluated the effectiveness of cefepime 2 g bd in combination with amikacin 7.5 mg/kg bd for the treatment of severe bacterial infection in 118 ICU patients, including 113 patients with nosocomial lower respiratory tract infections (LRTI) (mean age, 51 years). Ninety-six per cent (108/113) of the LRTI patients required respiratory assistance and 12% (14/113) had associated septicaemia/bacteraemia. Eighty-four per cent (95/113) had clinical signs of sepsis and 35% (39/113) had features of septic shock. The mean Simplified Acute Physiologic Score (SAPS) was 12 at inclusion. Seventy-nine patients with LRTI were clinically and bacteriologically evaluable. The causative pathogens were representative of those usually isolated in ICUs: Staphylococcus aureus (19%); Pseudomonas aeruginosa (14%); and Klebsiella, Enterobacter and Serratia spp. (17%). The clinical cure rate was 86% (68/79) while the pathogen eradication rate was 91% (107/117). Of the patients with associated septicaemia/bacteraemia, 89% (8/9) of the pathogens were eliminated. Cefepime-amikacin combination therapy was well tolerated; two patients discontinued treatment due to rashes. Combination therapy with cefepime 2 g bd and amikacin 7.5 mg/kg bd appears safe and effective for the treatment of nosocomial pneumonia in patients hospitalized in ICUs. Further comparative controlled studies are justified.

Evaluation of clinical judgment in the identification and treatment of nosocomial pneumonia in ventilated patients

To evaluate the accuracy of clinical judgment in the diagnosis and treatment of nosocomial pneumonia in ventilated patients, we studied 84 patients suspected of having nosocomial pneumonia because of the presence of a new pulmonary infiltrate and purulent tracheal secretions. We prospectively evaluated the accuracy of diagnostic predictions and therapeutic plans independently formulated by a team of physicians aware of all clinical, radiologic and laboratory data, including the results of Gram-stained bronchial aspirates. Definite (n = 51) or probable (n = 33) diagnoses could be established in all patients by strict histopathologic and/or bacteriologic criteria. Only 27/84 patients were diagnosed as having pneumonia. Organisms responsible for pneumonias were identified by quantitative cultures of samples obtained using a protected specimen brush or pleural fluid cultures. Four hundred eight predictions were made for the 84 studied patients. Clinical diagnoses for patients subsequently diagnosed as having pneumonia were accurate in 81/131 cases (62 percent). Furthermore, only 43/131 (33 percent) therapeutic plans proposed for these patients represented effective therapy. Common causes of inappropriate treatment included failure to diagnose pneumonia (50 plans), failure to effectively treat highly resistant organisms (21 plans), and failure to treat all organisms in cases of polymicrobial pneumonia (14 plans). Therapeutic plans formulated for patients without pneumonia included the unnecessary use of antibiotics in 45/277 cases (16 percent). These findings indicate that the use of clinical criteria alone does not permit the accurate diagnosis of nosocomial pneumonia in ventilated patients, and commonly results in inappropriate or inadequate antibiotic therapy for these patients.

Pharmacokinetics of cefodizime in elderly patients with moderate or severe renal impairment

In young adults, the elimination half-life of cefodizime is 3.5-4 h. A pharmacokinetic study was performed in eight patients, aged 63 to 85 years, divided into two groups with the following creatinine clearances (group I: greater than or equal to 50 ml/min and group II: less than 30 ml/min). Cefodizime was administered as a 1.0-g iv bolus. In group I, pharmacokinetic parameters did not differ from those observed in young healthy volunteers in a previous study. In group II, the half-life was increased (3.42-7.41 h). There is a linear correlation between the creatinine clearance and total clearance. The daily dose given needs to be based not on the age of the patient but on the degree of renal impairment. In elderly patients with severe renal impairment, the daily dose should be reduced if the creatinine clearance falls below 30 ml/min.

Characterization of distal bronchial microflora during acute exacerbation of chronic bronchitis. Use of the protected specimen brush technique in 54 mechanically ventilated patients

To obtain accurate information on distal bronchial microflora during acute exacerbation in patients with chronic bronchitis, we prospectively studied 54 such patients who had been receiving mechanical ventilation because of hypercapnic respiratory failure. Fiberoptic bronchoscopy using a protected specimen brush (PSB) was performed on each patient within the first 24 h after admission. Cultures of protected brush specimens demonstrated no growth in 27 patients (50%). With the exception of fever (38.2 +/- 0.8 versus 37.7 +/- 0.6 degrees C; p less than 0.05), the initial severity of the episode of exacerbation was similar in patients with and without infection. A total of 44 organisms were isolated in the 27 patients with positive cultures; the predominant pathogens were Hemophilus spp. and Streptococcus spp. (involved in 74% of cases), but other organisms were isolated in 12 of 27 patients. Mortality rates, duration of mechanical ventilation, and duration of hospitalization were not significantly different between patients with bronchial microflora treated with appropriate antimicrobial therapy (n = 27) and patients without bronchial microflora either receiving empirical antibiotic therapy (n = 18) or not (n = 9). These data suggest that distal bronchial infection due to the usual pathogens, as far as shown by protected specimen brush cultures, may not be the sole or even the predominant cause of acute exacerbation of chronic bronchitis in patients requiring mechanical ventilation.

Incidence and morbidity of cytomegaloviral infection in patients with mediastinitis following cardiac surgery

To determine the incidence and morbidity of infections with CMV associated with mediastinitis after conventional cardiac surgery, 115 consecutive adult patients with mediastinitis were evaluated with viral cultures of blood and urine. Shedding of CMV was seen in 29 patients (25 percent) within a mean period of 37 +/- 22 days after cardiopulmonary bypass. Viremia was documented in 79 percent (23) of these 29 patients. Acute renal failure and enzymatic abnormalities (AST and LDH) were significantly more common in patients with virologically proven infection with CMV (p less than 0.05). In patients who survived the initial period of bacterial infection, major differences in their clinical course were observed according to their virologic status. After the 15th day of hospitalization following the débridement, the persistence of local infection was more frequent (p less than 0.05) and the mortality was higher (p less than 0.01) in CMV-infected patients. Moreover, the mean duration of hospitalization in the ICU for survivors was 69 +/- 36 days in viral shedders, compared with 48 +/- 27 days in nonshedders (p less than 0.05). Infection with CMV in mediastinitis occurs frequently and is associated with persistence of local infection, prolonged hospitalization, and increased late mortality.

Nosocomial pneumonia in patients receiving continuous mechanical ventilation. Prospective analysis of 52 episodes with use of a protected specimen brush and quantitative culture techniques

Epidemiologic studies of nosocomial bacterial pneumonia in patients requiring mechanical ventilation have been limited because of the poor reliability of diagnosis procedures in this setting. To determine prognostic and descriptive factors of ventilator-associated (V-A) pneumonia, we prospectively studied 567 patients who had been receiving mechanical ventilation for more than 3 days in our unit. Fiberoptic bronchoscopy using a protected specimen brush (PSB) was performed on each patient suspected of having pneumonia because of the presence of a new pulmonary infiltrate and purulent tracheal secretions. The diagnosis of V-A pneumonia was retained only if PSB specimens yielded greater than 10(3) cfu/ml of at least one microorganism, unless this result was established to be a false positive result on follow-up. V-A pneumonia developed in 49 patients for a total of 52 episodes (9%). The actuarial risk of V-A pneumonia was 6.5% at 10 days, 19% at 20 days, and 28% at 30 days of ventilation. Patients with pneumonia were significantly older (65 versus 57 yr of age, p less than 0.01) and more frequently had severe underlying illnesses (24 versus 10%, p less than 0.01) than did patients without pneumonia. A total of 84 microorganisms (51 gram-negative and 33 gram-positive) were isolated in significant concentrations from PSB specimens. Pseudomonas aeruginosa and Staphylococcus aureus were involved in 31 and 33% of these pneumonias, respectively. Forty percent of all specimens yielded a polymicrobial flora with more than one potential pathogen.(ABSTRACT TRUNCATED AT 250 WORDS)

Study of the effects of liposomal amphotericin B on Candida albicans, Cryptococcus neoformans, and erythrocytes by using small unilamellar vesicles prepared from saturated phospholipids

We compared the anticellular effects of liposomal amphotericin B (AmB) formed from AmB and small unilamellar vesicles. The small unilamellar vesicles with or without cholesterol were prepared from three L-alpha-phosphatidylcholines with saturated acyl chains of different lengths: distearoyl (C18), dipalmitoyl (C16), and dimyristoyl (C14). We found that the anticellular potency of liposomal AmB, compared with that of free AmB, decreased with decreasing length of the acyl chain of the phospholipid and increased with the addition of cholesterol. In a parallel study (S. Jullien, A. Vertut-Croquin, J. Brajtburg, and J. Bolard, Anal. Biochem. 172:197-202, 1988), we found that binding of AmB to vesicles decreased with increasing length of the acyl chain of the phospholipid and decreased with the addition of cholesterol. We conclude that the anticellular effects of liposomal AmB preparations are due to the levels of AmB remaining free (unbound to the lipids) in these preparations.

Diagnosis of nosocomial pneumonia in intensive care unit patients

The optimal technique for diagnosing nosocomial bacterial pneumonia in critically ill patients cared for in the intensive care unit remains unclear, especially in the subgroup of patients requiring mechanical ventilation. An important advance has been the development of the protected specimen brush technique. We and others have demonstrated that secretions obtained using this technique and evaluated by quantitative cultures are useful in distinguishing patients with and without pneumonia. However, this procedure has important limitations in that results are not available immediately and in that a few false negative or false positive results may be observed. Recently, the use of bronchoalveolar lavage has been suggested to be of value in establishing the diagnosis of pneumonia, since the cells and liquid recovered can be examined microscopically immediately after the procedure and are also suitable for quantitative culture. We believe that microscopic identification of bacteria within cells recovered by lavage may provide a sensitive and specific means for early and rapid diagnosis of pneumonia in this setting and that the lavage technique can be conveniently incorporated into a protocol along with the quantitative culture of samples obtained using the protected specimen brush. This combination will probably improve the overall accuracy of diagnosis while allowing the administration of prompt empiric antimicrobial therapy in the majority of patients with pneumonia.

Diagnosis of nosocomial bacterial pneumonia in intubated patients undergoing ventilation: comparison of the usefulness of bronchoalveolar lavage and the protected specimen brush

PURPOSE

To compare the usefulness of specimens recovered using a protected specimen brush and those recovered by bronchoalveolar lavage in the diagnosis of nosocomial pneumonia occurring in intubated patients undergoing ventilation, we performed both procedures in patients suspected of having pneumonia because of the presence of a new pulmonary infiltrate and purulent tracheal secretions.

PATIENTS AND METHODS

Twenty-one patients (16 men and five women) with an average age of 57 +/- 12 years were studied. They had been receiving mechanical ventilation for 8 +/- 6 days before inclusion in the trial. The clinical suspicion for nosocomial bacterial pneumonia was high in these patients. Fiberoptic bronchoscopy was performed in each patient. Bronchoscopy specimens were obtained by a protected specimen brush and by bronchoalveolar lavage, and were then processed for quantitative bacterial and fungal culture using standard methods. Total cell counts were performed on an aliquot of resuspended original lavage fluid. Differential cell counts were made on at least 500 cells. In addition, 300 cells were examined at high-power magnification and the percentage of cells containing intracellular microorganisms and the average number of extracellular organisms per oil-immersion field were determined.

RESULTS

Quantitative culture of specimens recovered using the protected specimen brush were positive (more than 10(3) colony-forming units [cfu]/ml) in five of five patients with subsequently confirmed pneumonia, and negative (less than 10(3) cfu/ml) in 13 of 13 patients without bacterial pneumonia, but results were not available until 24 to 48 hours after the procedure. Quantification of intracellular organisms in cells recovered by lavage was also useful in distinguishing patients with pneumonia (more than 25 percent of cells with intracellular organisms in five of five patients) from those without pneumonia (less than 15 percent of cells with intracellular organisms in all cases), and results were available immediately. In contrast, quantitative culture of lavage fluid and differential cell counts were of little value in identifying infected patients.

CONCLUSION

The protected specimen brush and microscopic identification of intracellular organisms in cells recovered by lavage yield useful and complementary information, and together permit rapid and specific treatment of most patients with nosocomial pneumonia.

Detection of nosocomial lung infection in ventilated patients. Use of a protected specimen brush and quantitative culture techniques in 147 patients

To determine the usefulness of samples obtained by bronchoscopy using a protected specimen brush and evaluated by quantitative culture techniques in establishing the diagnosis of nosocomial pneumonia in patients requiring mechanical ventilation, we prospectively studied 147 ventilated patients suspected of having nosocomial pneumonia because of the presence of a new pulmonary infiltrate and purulent tracheal secretions. Positive cultures of protected brush specimens (greater than 10(3) cfu/ml) were found in only 45 patients (31%). Subsequent follow-up confirmed the diagnosis of pneumonia in 34 of 45 patients, and in only 4 of 45 patients was a positive culture firmly established to be a false positive result. No patient with less than 10(3) cfu/ml was subsequently shown to have had pneumonia, and the diagnosis was definitely excluded in 72 of 102 patients by the absence of pneumonia at autopsy or recovery without antibiotic therapy. In contrast, when 16 clinical variables were evaluated by stepwise logistic regression analysis, no combination could be identified that was useful in distinguishing patients with bacterial pneumonia. Furthermore, when the actual costs of evaluation and therapy of our patients were compared with the projected costs entailed in treating all patients suspected of having pneumonia with antibiotics, evaluation using the protected specimen brush and quantitative cultures was less expensive after only 6 days of treatment. These results suggest that the appearance of pulmonary infiltrates and purulent tracheal secretions does not result from bacterial pneumonia in a majority of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacokinetics of teicoplanin in critically ill patients with various degrees of renal impairment

The pharmacokinetics of teicoplanin were studied in 15 adult patients in the acute phase of severe infections caused by gram-positive cocci. All the subjects were given a daily intravenous bolus dose of 6 mg of teicoplanin kg-1 (body weight). The pharmacokinetic study was performed over a 48-h period after injection 4. The subjects were categorized according to their mean creatinine clearances (ml.min-1.kg-1) during the study period: group 1 (n = 3), greater than 1.6; group 2 (n = 6), 0.8 to 1.6; and group 3 (n = 6), 0.15 to 0.8. Mean concentrations of teicoplanin in serum at 1, 24, and 48 h were 33 +/- 8, 9 +/- 3, and 6 +/- 2.5 micrograms.ml-1, respectively. The mean half-lives of the concentration-time curve from 12 to 48 h were 28 +/- 4, 44 +/- 24, and 48 +/- 14 h in groups 1, 2, and 3, respectively (group 3 versus group 1: P less than 0.05). The mean area under the serum concentration-time curve from time zero to 24 h was 344 +/- 92 mg.h.liter-1, and the mean hybrid volume of distribution was 1.09 +/- 0.46 liter.kg-1. These values were similar for the three groups, with a trend for larger areas under the curve in group 3. Creatinine clearance correlated directly with the total body clearance of teicoplanin (r = 0.70) and with the renal clearance of teicoplanin (r = 0.82). However, in critically ill patients, the wide interindividual variations in pharmacokinetic parameters are more relevant than those related to the variations in renal function when creatinine clearance is above 0.30 ml.min-1.kg-1. We concluded that, in such conditions, monitoring of concentrations of teicoplanin in serum is mandatory.

Pharmacokinetic and pharmacodynamic interactions between nifedipine and propranolol or betaxolol

Pharmacokinetic and pharmacodynamic interactions between nifedipine and two beta-blocking agents were investigated. Eighty mg propranolol twice daily, and 20 mg betaxolol once daily, were randomly administered orally to six young healthy male volunteers, either singly for four days, or combined with nifedipine for the two subsequent days. Nifedipine had similar effects on the pharmacodynamics of both drugs. Nifedipine significantly enhanced propranolol bioavailability and Cmax, but reduced its tmax, in three out of six subjects who were also good absorbers of beta-blockers when taken alone. These effects might be due to enhanced intestinal absorption and/or enhanced first-pass effect, induced by nifedipine.

[Urinary tract obstruction by Candida bezoars, or fungus balls]

Two patients admitted to an intensive care unit for severe bacterial infection develops Candida albicans superinfection with obstruction of the urinary canals by "fungus balls". The development of medico-surgical techniques using antibiotics and immunosuppressive drugs accounts for the increasing incidence of disseminated candidiasis. The kidneys are particularly sensitive to Candida infections. Fungus balls are conglomerates of mycelium which may result in obstruction of the urinary tract. Their clinical, radiological and ultrasonic features, as well as the microbiological and serological diagnostic problems they raise are described. Ultrasonically guided percutaneous nephrostomy is a very interesting technique for the diagnosis of the condition and its local treatment by drainage and lavage with amphotericin B. This antifungal, combined with flucytosine is still used for the systemic treatment of candidiasis.

Use of granulated sugar in treatment of open mediastinitis after cardiac surgery

19 critically ill adults with acute mediastinitis after cardiac surgery were treated with granulated sugar, either directly (11 patients) or after failure of continuous irrigation (8 patients). Mediastinal tissue cultures were positive in 18 patients. Packing the mediastinal cavity with granulated sugar every 3 or 4 h resulted in near-complete debridement of the wound and rapid formation of granulation tissue in all patients and sterilisation of the wound after an average of 7.6 days. Dressings were easy and painless to change. 5/19 (26%) patients died before discharge, but none because of wound complications. The rest were discharged on average 54.2 days (range 29-120) after initial debridement of the wound; 11 underwent secondary surgical closure of the wound and in 3 the wound healed by granulation tissue formation alone. No recurrence of sternal infection has occurred after a mean follow-up of 8.2 months (range 3 to 17).

[Digitoxin poisoning: reversing ventricular fibrillation with Fab fragments of anti-digoxin antibody]

Purified Fab fragments of ovine anti-digoxin antibodies (Wellcome Foundation) were used to treat a patient who attempted suicide by absorbing 10 mg of digitoxin (serum concentration 265 micrograms/l). The poor prognosis, as assessed clinically and from serum potassium levels (7.5 mEq/l), seemed to warrant such a treatment. The weak (6.85%) cross-reactivity elicited in vitro between the anti-digoxin antibodies and digitoxin was compensated by increasing the doses, but improvement was observed with 3.6 g, i.e. about half the effective dosage initially considered. The criteria of effectiveness were clinical, electrocardiographic (reversal of the ventricular fibrillation), biochemical (simultaneous and opposite changes in extra- and intracellular potassium levels, suggesting that ATPase inhibition by digitalis is a reversible process) and toxicological: there was an increase in digitoxin serum levels suggesting displacement of the drug from tissue sites to plasma and other extracellular compartments where the Fab fragments are distributed, and Fab-bound digitoxin appeared fairly rapidly in the urine, which suggested shunting of the normal hepatic metabolic pathway.