Efficacy and safety of once-daily amikacin in combination with ceftazidime in critically ill adults with severe gram-negative infections.

Forty critically ill adult patients with severe Gram-negative infection were treated with once-daily amikacin combined with ceftazidime. The mean age was 56.6 +/- 19 years and mean APACHE II score was 22.7 +/- 6.6. Forty percent of patients required mechanical ventilation. The mean creatinine clearance at onset of therapy was 59.4 +/- 28 ml/min. All bacterial isolates were sensitive to amikacin. Fixed doses of amikacin 15 mg/kg, 12 mg/kg, and 8 mg/kg body weight were given once daily to patients with estimated creatinine clearance of > 80 ml/min., 50-80 ml/min., and < 50 ml/min, respectively. Forty-two causative gram-negative bacteria were isolated from 40 patients. The most common bacteria were Pseudomonas aeruginosa (18), and Escherichia coli (10). Overall clinical success and bacteriological eradication occurred in 85% and 87.5% of patients; 78.9% and 79% of patients with hospital-acquired infections; 90.5% and 95.2% of patients with community-acquired infections; and 62.5% and 81.3% of patients requiring mechanical ventilation, respectively. Therapeutic failure was documented in 15% of patients. Death due to infection was scored in two patients. The remaining were all due to persistence of the initial causative bacteria in patients with hospital-acquired infections. Persistence was documented with Ps. aeruginosa (2), Serratia spp. (1), and Acinetobacter spp. (1). Overall mortality occurred in 22.5% patients. Death unrelated to infection occurred in 7 patients. There was no clinical evidence of ototoxicity in any of our patients, however, nephrotoxicity was documented in 5%. In conclusion, once-daily amikacin combined with ceftazidime is practical, efficacious and probably safe in critically ill infected patients.

Diagnostic challenge of tuberculosis of the elderly in hospital: experience at a university hospital in Saudi Arabia.

We studied retrospectively 80 elderly patients who had been admitted to hospital with tuberculosis (TB) between January 1988 and June 1993. There were 64 with pulmonary TB and 16 with miliary tuberculosis (MTB). The mean age was 70+/-7.5 years (range 60-88 years) with 56% over 70 years of age. Underlying disease preceding TB was present in 86.3% patients. In the majority of patients clinical manifestations were subtle. Chest X-ray showed involvement of lower lung fields and miliary shadowing in 71.2% (33/80) and 20% (16/80) patients, respectively. The organism was detected in expectorated sputum specimens in 62.5% (50/80). Of the specimens obtained by flexible fibreoptic bronchoscopy (FOB), 61% were positive for acid-fast bacilli (AFB) by films and culture. Drug-induced adverse effects were observed in 17.6% (6/34). In 18 patients (22.5%), the diagnosis of TB was delayed or missed. The overall mortality of 21% (9/43) included seven patients with MTB and two with pulmonary TB. TB was the direct cause of death in the former and a significant contributory cause in the latter.

Coagulase-negative staphylococcal bacteraemia with special reference to septic shock: experience in an intensive care unit.

During a period of 4.5 years, 48 patients with bacteraemia due to coagulase-negative staphylococci were studied prospectively in order to evaluate their clinical profile, management and outcome. There were 25 males and 23 females with ages ranging between 13 and 100 years. Over 60% of patients belonged to the age group 30 to 69 years. Shock was recorded in 23 (48%) of the 48 patients. Of the shocked patients, 16 were immunocompromised and also had abnormal coagulation. Their mortality was 44%. By contrast, none of the immunocompromised patients without shock died. Abnormal coagulation was found in 17 patients without septic shock. Their mortality was 5.9%. The commonest underlying disease was respiratory failure especially in shocked patients. The source of infection was identified in the majority of cases. In addition, most patients had an indwelling intravascular catheter especially an arterial one. The overall mortality was 16.7% (8/48). It was significantly higher in patients with shock than in those without shock (30.4% vs. 4.0%, P < 0.05).

Infections in critically ill patients: experience in MICU at a major teaching hospital.

During a one-year period 105 patients suffering a total of 134 infectious episodes were studied prospectively in the medical intensive care unit (MICU). These patients included 54 male and 51 female patients, age ranging from 14 to 100 years (median = 54 years). The overall incidence of infection was 46.7%. Infections acquired in medical wards accounted for 47.8% of the total, followed by community-acquired infections in 27.0%, and MICU-acquired infections in 25.2% of the cases. The most frequent infections were pneumonia and septicaemia accounting for 88% of the total, whereas urinary tract (4.4%), gastrointestinal tract (5.0%), skin and wound infections (2.5%) constituted only 11.5%. The pathogens mainly involved were gram-negative rods, Staphylococcus spp. and Streptococcus pneumoniae. However, in community-acquired pneumonia, the major pathogens were gram-negative rods. In addition, Mycobacterium tuberculosis was an important cause of pneumonia in these patients. The majority of patients had a monoinfection; multiple pathogens were isolated in 11.9% of the episodes. The overall mortality was 46.7%. Several factors that influenced the mortality in these patients were analyzed. Early recognition of these factors may reduce morbidity and mortality.

Overwhelming respiratory failure associated with Legionella pneumophila.

Four patients were admitted to the medical intensive care unit at King Khalid University Hospital (KKUH) with overwhelming respiratory failure. Extensive investigations revealed serological evidence of Legionella infection. Three patients required intubation and mechanical ventilation. All patients received erythromycin; rifampin was added to two patients. Two patients survived and two patients died. We report, for the first time in Saudi Arabia, four cases of Legionella pneumophila with severe respiratory failure.

Re-evaluation of pneumonia requiring admission to an intensive care unit: a prospective study.

BACKGROUND: Appropriate treatment of severe community and hospital acquired pneumonias requiring admission to a medical intensive care unit depends on knowledge of the likely aetiological agents in any community. Little is known about the pattern and outcome of patients with such pneumonias in Saudi Arabia. METHODS: In a prospective study 113 patients with pneumonia were investigated in the medical intensive care unit at King Khalid University Hospital, Riyadh, Saudi Arabia between September 1991 and December 1992. The diagnosis was established by microscopy and culture of sputum, blood culture, or serological examination. A standard proforma was used to collect demographic, clinical, and laboratory data. RESULTS: A microbiological diagnosis was made in 80% of the cases with a single pathogen accounting for 69% of the isolates and multiple pathogens for 11%. Pseudomonas aeruginosa was the most common infecting agent (16%), followed by Streptococcus pneumoniae (12%), Staphylococcus aureus (9%), and Mycobacterium tuberculosis (8%). Pneumonia due to Legionella pneumophilia was diagnosed in three patients and infection due to Mycoplasma pneumoniae in two. These five cases were identified by serological examination. Gram negative rods were the predominant pathogens in both community and hospital acquired pneumonia. The aetiology of pneumonia was not identified in 20% of cases. The overall mortality was 37%. Patients with hospital acquired pneumonia had a higher mortality than those with a community acquired pneumonia. Similarly, a high mortality was found in patients who had a serious underlying disease, abnormal mental state, diastolic blood pressure < 60 mm Hg, blood urea > 7 mmol/l, abnormal liver function tests, serum albumin < 30 g/l, those who required mechanical ventilatory support, and those with APACHE II scores > 20. CONCLUSIONS: This study highlights two major findings which differ from previous reports on the aetiology of pneumonia. Firstly, Gram negative rods were the predominant pathogens in community acquired pneumonia and secondly, M tuberculosis was an important cause of pneumonia in these patients, indicating that tuberculous pneumonia should be considered in the differential diagnosis of pneumonia in Saudi Arabia.

Invasive evaluation of patients with heat stroke.

Right-heart catheterization was performed in ten patients who suffered heat stroke on their pilgrimage to Mecca, Saudi Arabia. The group included seven men and three women who had mean rectal temperatures of 42.4 degrees C. Other findings included the following: heart rate (mean, 120 beats/min); cardiac output (mean, 8.2 ml/min/m2); arterial pressure (mean, 65 mm Hg); cardiac indices (mean, 4.4 ml/min/m2); right atrial pressure (mean, 6 mm Hg); pulmonary capillary wedge pressure (mean, 10 mm Hg); systemic vascular resistance (mean, 684 dyne.s.cm-5); pulmonary vascular resistance (mean, 86 dyne.s.cm-5); oxygen delivery (mean 837 ml/min/m2); oxygen consumption (mean 160 ml/min/m2); mixed venous oxygen tension (mean, 56 mm Hg); and shunt fraction (mean, 20 percent). Nine patients survived. One, who had a cardiopulmonary arrest before any treatment could be administered, died.

Septic shock in critically ill patients: aetiology, management and outcome.

Over a period of 28 months, 45 episodes of septic shock from 83 episodes of bacteraemia were studied prospectively to evaluate their clinical profile, management and outcome. Thirty-six patients were studied, the overall incidence of septic shock being 54.2%. Gram-negative organisms accounted for 23 (51.1%) of such episodes, Gram-positive 17 (37.8%), and three episodes were polymicrobial (6.7%). The organisms isolated most frequently were Staphylococcus epidermidis (17.8%), Pseudomonas aeruginosa (13.3%), Escherichia coli and Klebsiella sp. (each 11.1%). Coagulation abnormalities were detected in 32 episodes (78%) and disseminated intravascular coagulation (DIC) occurred in 11 of these with high mortality. The most common underlying conditions were respiratory, hepatic and renal failures. The majority of these patients received crystalloids, colloids, vasopressor drugs and blood. Swan-Ganz catheters (SGC) were inserted on eight occasions, the majority of times indicating a hyperdynamic circulatory response. The overall mortality was 40%, despite aggressive management and intensive care. The most important factor in reducing mortality is early detection of bacteraemia and prompt management of these patients.

Evaluation of aztreonam in the treatment of serious gram-negative infections in a university hospital in Saudi Arabia.

The efficacy and safety of aztreonam were evaluated in an open trial at King Khalid University Hospital, Riyadh, Saudi Arabia. A total of 45 critically-ill adult patients were enrolled in the study. All patients with documented Gram-negative infection were treated with aztreonam as monotherapy. Antibiotics active against only Gram-positive and/or anaerobic organisms were allowed. Twenty cases were clinically evaluable. Eleven had lower respiratory tract infections (pneumonia), 3 had urinary tract infections, and 6 had septicemia. Clinical signs and symptoms, cultures and other laboratory profiles were assessed prior to treatment, at 4-6 days during treatment and within 2-3 days of the end of therapy (usually 7-15 days). Nineteen out of 20 (95%) had a satisfactory clinical response. All cases with septicemia and urinary tract infections were microbiologically cured. The overall microbiological response rate was 90%. Fifty-five percent of all infections were caused by Pseudomonas aeruginosa. Two patients with Gram-negative pneumonia due to P. aeruginosa did not respond microbiologically to aztreonam therapy. No serious adverse events requiring discontinuation of aztreonam therapy were reported. No mortality occurred.

Unusual radiologic manifestations of bronchogenic cyst.

We have presented four cases of bronchogenic cyst, emphasizing the uncommon radiologic manifestations, including air trapping and/or lobulated contour. Two of the cysts were in the lung parenchyma, one in the left hilum adherent to the left lower lobe bronchus, and one in the posterior mediastinum. Recognition of the unusual radiologic features aids in establishing an appropriate differential diagnosis and directing subsequent evaluation.

Widening of the subcarinal angle by pericardial effusion.

The subcarinal angle and transverse diameter of the cardiopericardial silhouette were measured on inspiratory posteroanterior radiographs of 54 patients (average age, 43.1 years) with pericardial effusion. The subcarinal angle was significantly greater (p less than 0.001) during effusion (81.0 degrees, n = 54) than either before (62.3 degrees, n = 14) or after (56.7 degrees, n = 21) effusion. A significant (p less than 0.05) positive correlation (r = 0.60, n = 118) was found between the magnitude of the subcarinal angle and the transverse diameter. This suggested that pericardial fluid accumulation displaces the heart and, in turn, splays the main bronchi. When pericardial fluid is not suspected clinically, a widened subcarinal angle, without other evidence of left atrial enlargement, may be a clue suggesting pericardial effusion.

Metastatic melanoma in the thorax: report of 130 patients.

Early detection of metastatic melanoma has become more important as newer and more effective therapeutic regimens are used. Between 1970 and 1980, 1,600 patients were treated at one institution for malignant melanoma. Of these, 260 (16.3%) developed thoracic metastasis. Satisfactory chest radiographs were available for analysis in 130 of 260 patients. The patterns of the intrathoracic metastasis include multiple pulmonary nodules (52 patients), solitary nodule (26), miliary pattern (two), mediastinal and/or hilar adenopathy (nine), pleural effusion (three), lytic bony lesions (one), extra-pleural mass (one), and combined lesions (36). Both the staging of melanoma and the radiographic pattern of thoracic metastasis seemed to prognosticate the survival rate of these patients. Miliary metastasis and bone destruction implied a grave prognosis. Patients with a solitary lung nodule had the best survival experience. Immunotherapy, chemotherapy, and surgery of selected distal metastases significantly improved the survival of most of these patients.

Pharyngoesophageal manifestations of epidermolysis bullosa.

Two cases of a rare hereditary disease, epidermolysis bullosa, congenital and acquired, are presented. The disease manifests by vesicular eruptions over the skin and mucous membrane of the oropharynx and oesophagus, alternating with sympton-free periods. The recurrent crops of vesicles heal by scarring and progressive stenosis of the pharynx and oesophagus. Although mucosal involvement is a less common and a late manifestation of the disease, it may occur in relatively mild cases and relatively early in the course of the disease. It is important that the radiologist be familiar with the pharyngoesophageal manifestations since the patient may present with dysphagia during an interval free of cutaneous lesions. The barium swallow appearance of stricturing with obstruction is illustrated.