Principles, practices and knowledge of clinicians when assessing febrile children: a qualitative study in Kenya.

BACKGROUND: Clinicians in low resource settings in malaria endemic regions face many challenges in diagnosing and treating febrile illnesses in children. Given the change in WHO guidelines in 2010 that recommend malaria testing prior to treatment, clinicians are now required to expand the differential when malaria testing is negative. Prior studies have indicated that resource availability, need for additional training in differentiating non-malarial illnesses, and lack of understanding within the community of when to seek care play a role in effective diagnosis and treatment. The objective of this study was to examine the various factors that influence clinician behavior in diagnosing and managing children presenting with fever to health centres in Kenya. METHODS: A total of 20 clinicians (2 paediatricians, 1 medical officer, 2 nurses, and 15 clinical officers) were interviewed, working at 5 different government-sponsored public clinic sites in two areas of Kenya where malaria is prevalent. Clinicians were interviewed one-on-one using a structured interview technique. Interviews were then analysed qualitatively for themes. RESULTS: The following five themes were identified: (1) Strong familiarity with diagnosis of malaria and testing for malaria; (2) Clinician concerns about community understanding of febrile illness, use of traditional medicine, delay in seeking care, and compliance; (3) Reliance on clinical guidelines, history, and physical examination to diagnose febrile illness and recognize danger signs; (4) Clinician discomfort with diagnosis of primary viral illness leading to increased use of empiric antibiotics; and (5) Lack of resources including diagnostic testing, necessary medications, and training modalities contributes to the difficulty clinicians face in assessing and treating febrile illness in children. These themes persisted across all sites, despite variation in levels of medical care. Within these themes, clinicians consistently expressed a need for reliable basic testing, especially haemograms and bacterial cultures. Clinicians discussed the use of counseling and education to improve community understanding of febrile illness in order to decrease preventable deaths in children. CONCLUSION: Results of this study suggest that since malarial testing has become more widespread, clinicians working in resource-poor environments still face difficulty when evaluating a child with fever, especially when malaria testing is negative. Improving access to additional diagnostics, continuing medical education, and ongoing evaluation and revision of clinical guidelines may lead to more consistent management of febrile illness by providers, and may potentially decrease prescription of unnecessary antibiotics. Additional interventions at the community level may also have an important role in managing febrile illness, however, more studies are needed to identify targets for intervention at both the clinic and community levels.

Can therapeutic drug monitoring optimize exposure to piperacillin in febrile neutropenic patients with haematological malignancies? A randomized controlled trial.

OBJECTIVES: The objectives of this study were to describe piperacillin exposure in febrile neutropenia patients and determine whether therapeutic drug monitoring (TDM) can be used to increase the achievement of pharmacokinetic (PK)/pharmacodynamic (PD) targets. METHODS: In a prospective randomized controlled study (Australian New Zealand Registry, ACTRN12615000086561), patients were subjected to TDM for 3 consecutive days. Dose was adjusted in the intervention group to achieve a free drug concentration above the MIC for 100% of the dose interval (100% fT>MIC), which was also the primary outcome measure. The secondary PK/PD target was 50% fT>MIC. Duration of fever and days to recovery from neutropenia were recorded. RESULTS: Thirty-two patients were enrolled. Initially, patients received 4.5 g of piperacillin/tazobactam every 8 h or every 6 h along with gentamicin co-therapy in 30/32 (94%) patients. At the first TDM, 7/32 (22%) patients achieved 100% fT>MIC and 12/32 (38%) patients achieved 50% fT>MIC. Following dose adjustment, 11/16 (69%) of intervention patients versus 3/16 (19%) of control patients (P = 0.012) attained 100% fT>MIC, and 15/16 (94%) of intervention patients versus 5/16 (31%) of control patients (P = 0.001) achieved 50% fT>MIC. After the third TDM, the proportion of patients attaining 100% fT>MIC improved from a baseline 3/16 (19%) to 11/15 (73%) in the intervention group, while it declined from 4/16 (25%) to 1/15 (7%) in the control group. No difference was noted in the duration of fever and days to recovery from neutropenia. CONCLUSIONS: Conventional doses of piperacillin/tazobactam may not offer adequate piperacillin exposure in febrile neutropenic patients. TDM provides useful feedback of dosing adequacy to guide dose optimization.

Acute mercury poisoning presenting as fever of unknown origin in an adult woman: a case report.

INTRODUCTION: Mercury intoxication may present in a wide range of clinical forms from a simple disease to fatal poisoning. This article presents a case of acute mercury poisoning, a rare condition that presents challenges for diagnosis with fever of unknown origin. CASE PRESENTATION: A 52-year-old Caucasian woman was admitted to the hospital with high fever, sore throat, a rash over her entire body, itching, nausea, and extensive muscle pain. She had cervical, bilateral axillary and mediastinal lymphadenopathies. We learned that her son and husband had similar symptoms. After excluding infectious pathologies, autoimmune diseases and malignancy were investigated. Multiple organs of our patient were involved and her fever persisted at the fourth week of admission. A repeat medical history elicited that her son had brought mercury home from school and put it on the hot stove, and the family had been exposed to the fumes for a long period of time. Our patient's serum and urine mercury levels were high. She was diagnosed with mercury poisoning and treated accordingly. CONCLUSIONS: Mercury vapor is a colourless and odorless substance. Therefore, patients with various unexplained symptoms and clinical conditions should be questioned about possible exposure to mercury.

Fever of unknown origin attributable to haematocolpos infected with Salmonella enterica Serotypetyphi resistant to nalidixic acid: a case report.

The prevalence of nalidixic acid-resistant Salmonella Typhi (NARST) infection is increasing worldwide. We are reporting an unusual case of infected haematocolpos presenting as urinary obstruction in a patient with fever of unknown origin (FUO). This case report highlights the importance of quinolone-resistant typhoid fever in the differential diagnosis of any acute febrile illness in countries, like India, where Salmonella infection is endemic.

High rate of breakthrough invasive aspergillosis among patients receiving caspofungin for persistent fever and neutropenia.

A number of agents are now available for empirical antifungal treatment (EAFT) of patients with persistent fever and neutropenia. We carried out a study of efficacy of antifungal drugs to prevent breakthrough invasive aspergillosis by reviewing the medical records of all consecutive patients who received EAFT from November 2005 to February 2006. Patients' characteristics and the type, dose and duration of antifungal therapy were recorded. Breakthrough invasive fungal infections were documented according to the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) definition. Fifty-six episodes of persistent fever with neutropenia requiring EAFT were recorded among 49 patients. All patients received high-dose chemotherapy for acute myeloid leukaemia (51%), acute lymphoid leukaemia (12%), lymphoma (14%) or other haematologic conditions (22%). Fourteen (29%) and five (10%) patients were allogeneic and autologous haematopoietic stem cell transplant recipients, respectively. Caspofungin was prescribed initially in 40 episodes (71%), amphotericin B (AmB) desoxycholate and liposomal AmB being prescribed in six (10%) and ten (18%) episodes, respectively. Six patients were switched from liposomal AmB to caspofungin because of adverse events. The median duration of antifungal therapy was 9 days. During follow-up, six patients (12%) were diagnosed with invasive aspergillosis after a median of 8 days (range 3-16 days) of EAFT. Invasive aspergillosis breakthrough occurred in 6/46 (13%) caspofungin recipients and in 0/16 (0%) AmB recipients (OR 3.1, p 0.32). The observed high rate of invasive aspergillosis among caspofungin recipients requires further evaluation.

Treatment-seeking for febrile illness in north-east India: an epidemiological study in the malaria endemic zone.

BACKGROUND: This paper studies the determinants of utilization of health care services, especially for treatment of febrile illness in the malaria endemic area of north-east India. METHODS: An area served by two districts of Upper Assam representing people living in malaria endemic area was selected for household survey. A sample of 1,989 households, in which at least one member of household suffered from febrile illness during last three months and received treatment from health service providers, were selected randomly and interviewed by using the structured questionnaire. The individual characteristics of patients including social indicators, area of residence and distance of health service centers has been used to discriminate or group the patients with respect to their initial and final choice of service providers. RESULTS: Of 1,989 surveyed households, initial choice of treatment-seeking for febrile illness was self-medication (17.8%), traditional healer (Vaidya)(39.2%), government (29.3%) and private (13.7%) health services. Multinomial logistic regression (MLR) analysis exhibits the influence of occupation, area of residence and ethnicity on choice of health service providers. The traditional system of medicine was commonly used by the people living in remote areas compared with towns. As all the febrile cases finally received treatment either from government or private health service providers, the odds (Multivariate Rate Ratio) was almost three-times higher in favour of government services for lower households income people compared to private. CONCLUSION: The study indicates the popular use of self-medication and traditional system especially in remote areas, which may be the main cause of delay in diagnosis of malaria. The malaria training given to the paramedical staff to assist the health care delivery needs to be intensified and expanded in north-east India. The people who are economically poor and living in remote areas mainly visit the government health service providers for seeking treatment. So, the improvement of quality health services in government health sector and provision of health education to people would increase the utilization of government health services and thereby improve the health quality of the people.

Waiting for microbiologic data to direct therapy against nosocomial infections in febrile surgical patients: are outcomes worsened?

HYPOTHESIS: Allowing adequate time for laboratory and culture results before initial treatment may be associated with a worse outcome in nosocomial infections. DESIGN: Cohort study of all episodes of nosocomial infection from December 10, 1996, to October 28, 1998. SETTING: Surgical services at a university hospital. PATIENTS AND METHODS: In surgical patients presenting with fever, 372 episodes of nosocomial infection were evaluated. Nosocomial infections were divided by time from fever to intervention (< or =12, 13-24, and >24 hours). These groups were subdivided by Acute Physiology and Chronic Health Evaluation II (APACHE II) scores into low (< or =10 [n = 114]), moderate (11-20 [n = 169]), and high severity of illness (>20 [n = 89]). Pneumonia and bloodstream infections were divided by APACHE II scores into low (< or =15 [n = 55 and n = 56, respectively]) or high severity of illness (>15 [n = 84 and n = 77, respectively]). MAIN OUTCOME MEASURES: Mortality, length of stay. RESULTS: No difference in outcome was seen between different time intervals from fever to intervention for nosocomial infections in patients with APACHE II scores of no more than 10. Patients treated more than 24 hours after fever were significantly younger than those treated at no more than 12 and 13 to 24 hours with APACHE II scores of 11 to 20 (P<.05) and more than 20 (P<.05). Mortality and length of stay for patients treated at later time intervals were comparable with those of patients treated earlier with similar APACHE II scores. There was no difference in outcome for patients with pneumonia or bloodstream infection. CONCLUSIONS: Episodes of infection in which treatment was withheld until initial microbiologic data were available (24 hours) did not have worse outcomes compared with those treated earlier. Waiting for laboratory and culture results to direct antibiotic therapy for nosocomial infections does not appear harmful and may be potentially beneficial.

Empiric antimicrobial therapy of febrile neutropenic patients undergoing haematopoietic stem cell transplantation.

This study was conducted to assess the efficacy and toxicity of intravenous (i.v.) ceftazidime and ciprofloxacin in neutropenic febrile patients undergoing high dose myeloablative therapy and hematopoietic stem cell transplantation (HSCT). All patients undergoing HSCT for leukaemia, lymphoma, multiple myeloma and solid tumours received open-label ceftazidime 2 g i.v. every 8 h and ciprofloxacin 400 mg i.v. every 12 h if they developed fever while they were neutropenic. Success with or without modification of this regimen was defined as survival through the neutropenic period; failure was defined as death secondary to infection. Of 106 patients treated with this regimen, the success rate was 99%. Sixty-one of the patients (57.5%) defervesced within 48-72 h and remained afebrile without regimen modification. In 41.5% of the cases (44/106), the regimen was modified because of persistent fever. One patient died secondary to sepsis. The combination of ceftazidime and ciprofloxacin as initial empiric antibacterial therapy in febrile neutropenic patients undergoing myeloablative therapy and HSCT is highly effective and is associated with minimal toxicity.

Ceftazidime in combination with glycopeptide antibiotic is an effective first-line therapy for patients undergoing high-dose therapy with autologous peripheral blood stem cell support.

It was the objective of this study to evaluate the efficacy and toxicity of an empirical antibiotic therapy consisting in ceftazidime and a glycopeptide antibiotic. All patients enrolled in the study had hematological malignancies and underwent high-dose therapy with peripheral blood stem cell (PBSC) support. In this retrospective study, 183 of 207 patients who had received a PBSC-supported high-dose therapy were evaluable. Any patients who had fever higher than 38.5 degrees C received ceftazidime in combination with vancomycin (105 patients) or teicoplanin (69 patients). In 80 of 174 patients with fever (45%) the fever resolved within 72 h as a result of the treatment with ceftazidime and the glycopeptide antibiotic. In nonresponding patients, the changes included the replacement of ceftazidime by imipenem/cilastin (94 patients) and the addition of erythromycin (12 patients) or metronidazole (3 patients). Amphotericin B was administered in 29 patients. Following hematological reconstitution, the fever and clinical signs, including radiographic findings, resolved in 20 primarily nonresponding patients. In blood cultures, a significantly higher incidence of gram-positive than of gram-negative bacteria was observed (26 vs 7). The toxicity of the first-line antibiotic therapy was limited to allergic skin reactions in 12 patients. Ceftazidime in combination with a glycopeptide antibiotic provides an effective and safe first-line therapy for patients with neutropenic fever following PBSC-supported high-dose therapy.

A double-blind comparison of empirical oral and intravenous antibiotic therapy for low-risk febrile patients with neutropenia during cancer chemotherapy.

BACKGROUND: Among patients with fever and neutropenia during chemotherapy for cancer who have a low risk of complications, oral administration of empirical broad-spectrum antibiotics may be an acceptable alternative to intravenous treatment. METHODS: We conducted a randomized, double-blind, placebo-controlled study of patients (age, 5 to 74 years) who had fever and neutropenia during chemotherapy for cancer. Neutropenia was expected to be present for no more than 10 days in these patients, and they had to have no other underlying conditions. Patients were assigned to receive either oral ciprofloxacin plus amoxicillin-clavulanate or intravenous ceftazidime. They were hospitalized until fever and neutropenia resolved. RESULTS: A total of 116 episodes were included in each group (84 patients in the oral-therapy group and 79 patients in the intravenous-therapy group). The mean neutrophil counts at admission were 81 per cubic millimeter and 84 per cubic millimeter, respectively; the mean duration of neutropenia was 3.4 and 3.8 days, respectively. Treatment was successful without the need for modifications in 71 percent of episodes in the oral-therapy group and 67 percent of episodes in the intravenous-therapy group (difference between groups, 3 percent; 95 percent confidence interval, -8 percent to 15 percent; P=0.48). Treatment was considered to have failed because of the need for modifications in the regimen in 13 percent and 32 percent of episodes, respectively (P<0.001) and because of the patient's inability to tolerate the regimen in 16 percent and 1 percent of episodes, respectively (P<0.001). There were no deaths. The incidence of intolerance of the oral antibiotics was 16 percent, as compared with 8 percent for placebo (P=0.07). CONCLUSIONS: In hospitalized low-risk patients who have fever and neutropenia during cancer chemotherapy, empirical therapy with oral ciprofloxacin and amoxicillin-clavulanate is safe and effective.

Safety and toxicity of amphotericin B in glucose 5% or intralipid 20% in neutropenic patients with pneumonia or fever of unknown origin: randomised study.

OBJECTIVE: To compare the feasibility of treatment, safety, and toxicity of intravenous amphotericin B deoxycholate prepared in either glucose or intralipid for empirical antimycotic treatment of neutropenic cancer patients. DESIGN: Single centre stratified, randomised non-blinded phase II study. SETTING: University hospital providing tertiary clinical care. SUBJECTS: 51 neutropenic patients (leukaemia (35), lymphoma (11), solid tumours (5)) with refractory fever of unknown origin (24) or pneumonia (27). INTERVENTIONS: Amphotericin B 0.75 mg/kg/day in 250 ml glucose 5% solution or mixed with 250 ml intralipid 20%, given on eight consecutive days then alternate days, as a 1-4 hour infusion. MAIN OUTCOME MEASURES: Feasibility of treatment, subjective tolerance (questionnaire), and objective toxicity (common toxicity criteria of the National Cancer Institute). RESULTS: Study arms were balanced for age, sex, underlying malignancy, renal and liver function, and pre- and concomitant treatment with antibiotics and nephrotoxic agents. No statistically significant or clinically relevant differences were found between the treatment groups for: daily or cumulative dose and duration of treatment with amphotericin B; incidence and time of dose modifications or infusion duration changes related to toxicity; dose or duration of symptomatic support with opiates, antipyretics, or antihistamines; renal function; subjective tolerance; most common toxicity scores; course of infection; and incidence of treatment failures. Patients treated with amphotericin B in intralipid were given fewer diuretics (P<0.05) and therefore had more peripheral oedema (P<0.01) and needed less potassium supplementation (P<0.05) than patients given amphotericin in glucose. Acute respiratory events were more common in the intralipid arm (P<0.05). CONCLUSIONS: Amphotericin B 0.75 mg/kg/day in intralipid given on eight consecutive days then alternate days provides no benefit and is associated with potential pulmonary side effects possibly because of fat overload or an incompatibility of the two drugs.

Discontinuation of intravenous antibiotic therapy during persistent neutropenia in patients receiving prophylaxis with oral ciprofloxacin.

To evaluate the mortality and morbidity associated with early discontinuation of intravenously administered antibiotics, we prospectively examined the incidence and cause of recurrent fever in patients with persistent neutropenia who responded to a short course of intravenous antibiotic therapy. Preventive measures included the use of oral ciprofloxacin as prophylaxis for infection by gram-negative bacteria during the entire neutropenic episode. The rate of response to either initial or modified intravenous antibiotic therapy was 96% (149 of 156 episodes of fever). Eighty-five patients had an episode of persistent neutropenia (median duration, 7 days; range, 1-36 days) after they responded to treatment. Seven of these patients had recurrent fever, including 2 with bacteriologically documented infections, 4 with probable fungal pneumonia, and 1 with documented pneumonia due to Aspergillus fumigatus. Two patients with probable fungal pneumonia died, while the other infectious episodes resolved completely. These results do not support the continuation of intravenous antibiotic therapy for febrile patients with persistent neutropenia who have responded to the antibiotic regimen while receiving prophylaxis with oral ciprofloxacin.

Randomized trial comparing oral ciprofloxacin plus penicillin V with amikacin plus carbenicillin or ceftazidime for empirical treatment of febrile neutropenic cancer patients.

Aminoglycoside-containing combination therapy has been the standard empirical approach for febrile neutropenic cancer patients. With the advent of the broad-spectrum oral fluoroquinolones, it is now possible to evaluate an initial empirical alternative therapy. A prospective randomized study was conducted comparing oral ciprofloxacin plus penicillin V (group A) with amikacin plus carbenicillin or ceftazidime (group B). Main criteria for eligibility were febrile patients with solid tumor or nonlymphoblastic lymphoma, a Zubrod PS equal to 1 or 2, no diarrhea, mucositis, or long-term central venous catheter. A total of 108 consecutive neutropenic febrile episodes were randomized (5 exclusions); 55 episodes were assigned to group A and 48 to group B. Most febrile episodes were of unknown origin. There were 10 microbiologically documented episodes with two cases of bacteremia. Both regimens were well tolerated. Oral regimen was substantially cheaper than parenteral regimen. Treatment success without regimen modification was 94.5% for group A and 93.8% for group B (p = .86; CI -0.08-0.10). Oral therapy with ciprofloxacin and penicillin V is a safe alternative to standard parenteral therapy in this low-risk group of neutropenic patients, with unquestionable cost containment.

Non-responsiveness to antimicrobial therapy.

During the course of treating patients the clinician is faced with the problem of non-response to drugs. The expected therapeutic benefit is not observed. The cause may lie in the diagnosis, sub-type of disease, in the resistance of invading micro-organism or the drug itself. The drug dose, frequency, duration, mode of administration, compliance may be inadequate, inappropriate; the patient's pharmacokinetic profile may be unexpected, unusual; there may be alteration in the receptor, population, type, compensatory mechanism of the body etc. The relative importance of the host, parasite and drug related factors varies with disease, type of patient and drug under consideration. In the second section of the Clinical Pharmacology series, the causes of non-responsiveness to drugs will be discussed with reference to a few common diseases. The principles are applicable to may others.

Comparison of imipenem versus cefuroxime plus tobramycin as empirical therapy for febrile granulocytopenic patients and efficacy of vancomycin and aztreonam in case of failure.

143 aplastic episodes with fever in 91 haematological patients with granulocytopenia were treated empirically in a randomized prospective study using either imipenem (Imi) or a combination of tobramycin and cefuroxime (T/C). Response after 72 h was significantly better in patients receiving Imi (44/75 vs 27/68, p < 0.05). This was seen especially in patients with bacteriologically proven infections where the isolated staphylococci and streptococci were more susceptible to Imi. In both groups, patients who failed to respond to the initial antibiotic therapy were given vancomycin and aztreonam (V/A). The response rate after another 72 h, measured using the same criteria as after the first 72 h, did not differ statistically between the groups. One patient in each study group died from the bacterial infection, both from Gram-positive bacteraemia. Duration of fever was significantly shorter in the Imi group (4 days vs 7 days, p < 0.04). Serum peak and trough concentrations of the antibiotics were comparable. Both regimens were well tolerated. Our results show that monotherapy with imipenem is superior to the combination of tobramycin and cefuroxime during the first 72 h of therapy and can be safely administered to neutropenic patients with predominantly Gram-positive infections. A combination of vancomycin and aztreonam, given when initial imipenem treatment has failed, was effective in only a few patients. Adjuvant glycopeptide therapy from the outset in the treatment of febrile granulocytopenic patients did not seem worthwhile.

Síndrome febril de difícil diagnóstico

Presentamos 38 casos de síndrome febril de difícil diagnóstico evaluados en el lapso de dos y medio años en el Hospital Militar Central de Bogotá. Se encontraron como causas más frecuentes las de origen infeccioso (52.63 por ciento), seguidas de las de origen neoplásico e inmune (15.78 por ciento) cada una. Sin diagnóstico quedaron cinco pacientes (13.15 por ciento). Se revisa el tema y se compara con trabajos nacionales y de otros paises.

Options and limitations of long-term oral ciprofloxacin as antibacterial prophylaxis in allogeneic bone marrow transplant recipients.

The efficacy and safety of ciprofloxacin as long-term antibacterial prophylaxis after allogeneic bone marrow transplantation were assessed prospectively. Eighty-nine recipients of lymphocyte-depleted marrow grafts were each given ciprofloxacin orally, 500 mg twice daily. Fever developed in 71 out of 78 evaluable patients (91%) and was accompanied by positive blood cultures in 42 cases (59%). 'Viridans' streptococci, all but one with reduced in vitro susceptibility to ciprofloxacin, accounted for 35 episodes of bacteraemia. Thirty-three episodes occurred in patients given anthracyclines compared with only two episodes in other patients (chi 2 = 5.58: p less than 0.05). All bacteraemic fevers occurred within 11 days post-transplant. Gram-negative sepsis did not occur in any patient. Sixteen patients died but none due to a bacterial cause. Allergy to ciprofloxacin was registered in three out of 76 assessable cases (4%).

Imipenem/cilastatin as initial therapy for febrile neutropenic patients.

Imipenem 2 g daily was administered intravenously to 40 evaluable patients with neutropenia and fever. Twenty-three patients had acute leukaemia and 17 malignant lymphoma. The overall response rate was 70.0%. Of the 14 patients with documented infection, 9 (64.3%) responded. Poorer responses were observed in patients with pneumonia (40%) or pseudomonal infection (50%). The response rate was significantly higher among patients with increasing neutrophil counts during therapy (P less than 0.02). Fungal infection was a common cause of treatment failure. Gastrointestinal side effects and skin rashes were occasionally seen. No patient developed central nervous system toxicity. Imipenem is a practical alternative to antibiotic combinations for management of neutropenic infection. However, careful monitoring is essential in the subgroups of patients with pneumonia or pseudomonal infections, who may require modifications of therapy.

A randomized study of tobramycin plus ticarcillin, tobramycin plus cephalothin and ticarcillin, or tobramycin plus mezlocillin in the treatment of infection in neutropenic patients with malignancies.

Two hundred twenty-five patients with 358 febrile episodes were treated with tobramycin and ticarcillin (TT), tobramycin and mezlocillin (TM), or tobramycin, ticarcillin and cephalothin (TTC). There were no statistically significant differences in the response rates for patients who were proven to have infection (67% with TT, 69% with TTC and 53% with TM). Patients were more often cured of their infection if their neutrophil count rose during therapy. In this study, the addition of cephalothin to TT did not increase the frequency of azotemia (10% and 12%, respectively). Although mezlocillin has a broader spectrum of activity in vitro than ticarcillin, it was not more efficacious when combined with tobramycin than ticarcillin plus tobramycin for the treatment of infections in neutropenic patients.