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E V Haldane

Publications and source records attributed to E V Haldane.

At least 19 recordsLinked to original sources

Community-acquired pneumonia requiring hospitalization. Is it different in the elderly?

The authors studied 138 patients, 57 of whom were younger than 65 years of age and 81 who were 65 years of age and older, with community-acquired pneumonia to determine whether or not such pneumonia is different in the elderly and to define how such patients are investigated and treated. Pneumonia in the elderly was characterized by a higher mortality, 30 v 10%; more likely to be of unknown etiology, 54 v 30%; and more likely to show radiographic progression after the patient had been admitted to the hospital, 48 v 11%. In addition, elderly patients were more likely to be afebrile when admitted, 57 v 26%. Twenty-seven etiologic categories were present in 77 patients in whom a cause for the pneumonia was established. Streptococcus pneumoniae accounted for 9.4% of the pneumonia overall and for 27% of the pneumonia among patients who had sputum cultures performed before antibiotic therapy. The diagnostic yield was 11.6% for blood cultures, 38.2% for sputum cultures, 2.3% for throat washing, and 22.1% for serological studies. Twenty-seven percent of patients were receiving antibiotics of the time of admission to the hospital. Most (79%) received more than one antibiotic after admission. This study indicates that community-acquired pneumonia is a serious illness and that an algorithm approach to diagnosis and treatment of such pneumonia is necessary.

Aged↗

Seroepidemiology of Q fever among domestic animals in Nova Scotia.

We used the indirect microimmunofluorescence test to determine the presence of antibodies in sheep, cattle, goat, cat, and dog sera to phase I and II Coxiella burnetii antigens in Nova Scotia. Only 6.7 per cent of the 329 sheep tested had antibodies to phase II antigen and none had antibodies to phase I. Of 29 goats tested, 7 per cent and 3.5 per cent had antibodies to phase II and phase I antigens, respectively. In contrast, 23.8 per cent of the 214 cattle tested had antibodies to phase II antigen, and 24.2 per cent had antibodies to phase I antigen; 24.1 per cent of 216 cats tested had antibodies to phase II antigen and 6 per cent had antibodies to phase I antigen. None of the 447 dogs tested had antibodies detected. We conclude that cattle and cats may be reservoirs for human Q fever in Nova Scotia.

Animals↗

Does cytomegalovirus play a role in community-acquired pneumonia?

Cytomegalovirus (CMV) is recognized as an important pathogen in the immuno-suppressed patient. Sporadic case reports of cytomegalovirus community-acquired pneumonia have appeared. We studied 443 patients with community-acquired pneumonia requiring hospitalization to define the role of cytomegalovirus in this illness. Four patients (0.9%) had good evidence that cytomegalovirus caused their pneumonia: 2 had the virus isolated from pulmonary tissue and 2 had cytomegalovirus inclusion bodies visualized in this tissue. An additional 14 patients had serologic evidence (a fourfold rise in the complement fixation tests) of cytomegalovirus infection. Analysis of these 18 patients suggest, that cytomegalovirus plays a role in community-acquired pneumonia. Six (33%) of the patients were immunosuppressed. Six others had concomitant infections: Chlamydia trachomatis (3); Epstein-Barr virus and M. pneumoniae (1); and bacteremia with Group B streptococcus and Bacteroides fragilis plus Eubacterium lentum (1 each). Seven patients (39%) required assisted ventilation, four of whom developed secondary bacterial pneumonia. Five (28%) died. Only two patients had a clinical and radiographic picture suggestive of a viral illness as a cause of the pneumonia. Three patients had atypical lymphocytes in their peripheral blood film. We found that the prevalence of complement fixing antibody to cytomegalovirus increased with age. Such antibody was lacking among those in the 16-20 year group while it peaked at 65% for males and at 78% for females ages 91-100 years. Despite the fact that 42.2% of the adults lacked antibody to cytomegalovirus, community-acquired pneumonia due to this virus is uncommon and does not justify routine serological testing for such infection among patients with community-acquired pneumonia.

Adult↗

Seroepidemiology of Q fever in Nova Scotia and Prince Edward Island.

The prevalence of Coxiella burnetti infection (Q fever) was determined among Nova Scotia (N.S.) and Prince Edward Island (P.E.I.) blood donors by using the complement fixation and microimmunofluorescence (IF) test. The complement fixation and IF antibody tests measured antibody prevalence for the phase II or phase I and II antigens, respectively. Complement-fixing antibodies to phase II antigen were detected in 4.1% of 997 N.S. and 5.0% of 219 P.E.I. blood donors. Anti-phase II antibodies were detected by microimmunofluorescence in 11.8 and 14.6% of the blood donors in the two provinces, respectively. Anti-phase I antibodies were detected among 2.8% of the N.S. blood donors and 6.3% of the P.E.I. blood donors. Comparison of rates of anti-phase II IF by counties in N.S. revealed that there was at least one county where infection by C. burnetti is hyperendemic. Rates of antibody prevalence were similar in all three areas of P.E.I. examined. We conclude that "Q fever" is endemic in N.S. and P.E.I. and that the microimmunofluorescence test is more suitable than the complement fixation test for seroepidemiologic studies.

Adolescent↗

Endocarditis due to Q fever in Nova Scotia: experience with five patients in 1981-1982.

Q fever endocarditis is rarely reported in North America; only four cases have been documented since 1953. In 1981-1982, five cases were identified in the Victoria General Hospital, Halifax, Nova Scotia. Four patients were from widely separated areas of Nova Scotia and one was from Prince Edward Island. Four patients with long-standing valvular abnormalities, including two with prosthetic valves, presented with recurrent febrile episodes. The fifth patient, who was previously well, had recurrent septic embolic episodes. Clinical features and laboratory findings were variable. Diagnosis by serology was confirmed in four patients by culture of Coxiella burnetii from excised tissue. Histopathology varied from nonspecific inflammatory changes to two more distinctive patterns; electron microscopy showed C burnetii in two patients. Therapy with tetracycline and trimethoprim-sulfamethoxazole was beneficial, although three patients required valve replacement for hemodynamic deterioration. Q fever endocarditis may be more common than is recognized, and serological investigations should be performed in all cases of culture-negative endocarditis.

Adult↗

Ataxia in Listeria monocytogenes infections of the central nervous system.

From 1976 to 1981 Listeria monocytogenes was second only to Neisseria meningitidis as the cause of bacterial infections of the central nervous system in adults at our hospital. None of the patients with Listeria infection was immunosuppressed or had an underlying malignancy. Ataxia was an initial feature in five of the eight patients, and in three of them it persisted beyond their discharge from the hospital. Ataxia was not a feature of the clinical picture of 14 other adult patients with meningococcal and pneumococcal meningitis. Our data indicate that L monocytogenes should be suspected as the etiologic agent in an adult with ataxia and infection of the central nervous system.

Adult↗

Q fever in maritime Canada.

Only nine cases of Q fever were recorded in Canada in the 20 years prior to 1978. In the 18 months from August 1979 to January 1981 the disease was diagnosed serologically in six patients from the Maritime provinces. All were epidemiologically unrelated and none had been exposed to animals. Five had pneumonia and one had chronic Q fever with probable prosthetic valve endocarditis. Three of the five pneumonia patients presented with signs and symptoms of an acute lower respiratory tract infection and were indistinguishable clinically from other patients with atypical pneumonias. The other two with pneumonia presented with nonresolving pulmonary infiltrates and complained of decreased energy. Four of the five pneumonia patients responded well to treatment with erythromycin; the fifth required two courses of tetracycline. The patient with chronic Q fever had a large amount of cryoglobulins in his serum and evidence of immune complex disease. These cases indicate that Q fever should be considered as a possible cause of atypical pneumonia in Canada.

Adult↗

Clostridium difficile: epidemiology and clinical features.

To determine the epidemiologic features of Clostridium difficile in Halifax, Nova Scotia, the authors studied two groups of hospitalized patients, one group of outpatients and a fourth group of 54 healthy subjects. The first group consisted of 29 patients with diarrhea, whose stool was found to contain C. difficile or its cytotoxin, or both. Twenty-two underwent sigmoidoscopic examinations; of these, 18 had abnormal colonic mucosa and 6 of the 18 had pseudomembranous colitis. In the second group of 127 patients on general medical wards, 22 (17%) carried C. difficile. Thirteen of the 22 had diarrhea, and 3 had pseudomembranous colitis. Clustering of patients with C. difficile was evident. In vitro production of toxin by isolates of C. difficile from these patients was more likely if antibiotics had been given. Only 1 (4.5%) of the 22 outpatients with various gastrointestinal disorders (group 3) and none of the 54 healthy subjects (group 4) carried C. difficile. The clinical spectrum of infection with C. difficile extended from asymptomatic patients to those with nonspecific colitis and pseudomembranous colitis.

Adult↗

Causes of atypical pneumonia: results of a 1-year prospective study.

In a protocol study of cases of atypical pneumonia over a 1-year period an etiologic agent was established in 16 cases: Legionella pneumophila in 8, Coxiella burnetii in 3, Chlamydia trachomatis in 2, Mycoplasma pneumoniae in 1, para-influenza 3 virus in 1 and cytomegalovirus in 1. In the remaining 11 cases no agent was identified; the illnesses in these cases tended to be less severe. The pneumonia took much longer to resolve in the patients with Legionnaires' disease than in all the other patients (mean interval from onset of symptoms to clearing of the chest roentgenogram: 69 days v. an average of 16 days). However, the length of stay in hospital was similar for the three groups: those with Legionnaires' disease, those with atypical pneumonia of unknown cause and those with atypical pneumonia of various other established causes. L. pneumophila infection may explain a proportion of atypical pneumonias that previously could not be diagnosed, although in this series the cause of 41% of the pneumonias remained unexplained.

Chlamydia Infections↗

Resistance to aminoglycoside antibiotics of gram-negative bacilli isolated in Canadian hospitals.

A survey was made of the frequency of resistance to amikacin, gentamicin and tobramycin among aerobic gram-negative bacilli isolated over a 4-week period in 1979 at six large, geographically separated Canadian hospitals. In the entire series of 4407 isolates the frequency of resistance was 2.5% to amikacin, 8.1% to gentamicin, 5.9% to tobramycin and 1.7% to all three. Most (81%) of the resistant bacteria were acquired by the patients after admission to hospital. The frequency of resistance to the three aminoglycoside antibiotics in each hospital largely reflected the local rate of cross-infection by endemic strains of resistant bacteria.

Amikacin↗

Susceptibility of anaerobic bacteria to nine antimicrobial agents and demonstration of decreased susceptibility of Clostridium perfringens to penicillin.

The activity of moxalactam, cefoxitin, cephalothin, cefamandole, chloramphenicol, clindamycin, metronidazole, and ticarcillin was determined against 344 isolates of anaerobic bacteria. The activity of penicillin G was determined as well for 234 isolates not of the Bacteroides fragilis group. Moxalactam was more active than cephalothin and cefamandole and slightly less active than cefoxitin. Metronidazole was the most active antimicrobial agent against the B. fragilis group, whereas chloramphenicol was most active overall. Clostridium species were the most resistant group of organisms tested. Relatively high concentrations of penicillin were required to inhibit the C. perfringens strains: 80% at 0.5 U/ml and 100% at 16 U/ml. Our study demonstrates the need for periodic anaerobe susceptibility testing in order to better guide empiric antibiotic therapy.

Anaerobiosis↗

Hemolysin and K antigens in relation to serotype and hemagglutination type of Escherichia coli isolated from extraintestinal infections.

Escherichia coli isolated from cases of bacteremia and from a variety of urinary tract infections were characterized according to serotype (O:H antigenicity), K type (possession of K1, K2, K3, K12, or K13), hemagglutination (HA) type, and production of beta-hemolysin. Results obtained with the bacteremia and urinary tract infection isolates were similar except for more hemolytic isolated from urine than from blood (42 versus 29%) and more K1+ isolates from blood than from urine (50 versus 29%). A close correlation was found between Ha type VI (production of fimbriae which mediate mannose-resistant HA of human and African green monkey erythrocytes) and the production of hemolysin or K1 capsular antigen or both. Most (95 of 98, or 95%) of the HA type VI+ blood isolates and most (146 of 164, or 89%) of the HA type VI+ urine isolates produced hemolysin or K1 or both, in contrast to 22 and 26%, respectively, of those belonging to HA types other than HA type VI. Also, 76% of all hemolytic and 70% of all K1+ isolates belonged to HA type VI. Remarkably few of the HA type VI+ isolates (13%) and even fewer of the HA type VI- isolates (3%) produced both K1 and hemolysin; these belonged mainly to serotypes O16:H6, O18:H7 and O2:H4. Other major serogroups were usually K1+/hemolysin- (O1, O7) or K1-/hemolysin+ (O2, O4, O6). At least 74% (262 of 351) and possibly as many as 83% (293 of 351) of those isolates which produced mannose-resistant HA of human erythrocytes were classified as HA type VI+; 31 isolates produced mannose-resistant HA with all erythrocytes tested. Taking serogroup and serotype into consideration, we conclude that the E. coli fimbrial hemagglutinin(s) responsible for the HA type VI phenotype will prove to be the same as the virulence-associated mannose-resistant adhesins of uropathogenic E. coli which other investigators have characterized as unique fimbrial antigens detectable by mannose-resistant HA of human erythrocytes.

Antigens, Bacterial↗

Evaluation of cerebrospinal fluid lactic acid levels as an aid in differential diagnosis of bacterial and viral meningitis in adults.

The level of lactic acid in cerebrospinal fluid has been suggested as a useful diagnostic parameter to differentiate between bacterial and viral meningitis, especially in patients partially treated before admission to hospital. A concentration of greater than or equal to 35 mg/dl, determined by either gas-liquid chromatography or an enzymatic method, has been considered in several studies to provide definite evidence of meningitis of bacterial origin, whereas a lower level indicates no bacterial involvement. Over the past 18 months, we have analyzed by the enzymatic method the lactate level in 493 spinal fluids submitted from 434 adult patients with various conditions involving the central nervous system. Fifty fluids had a lactate level of greater than 35 mg/dl, of which 19 were cases of infective meningitis of varying etiology. The 435 specimens with lactate levels within the range considered normal included three cases of infective meningitis, of which two were cryptococcal and one was bacterial. In this adult study, the lactate level in the cerebrospinal fluid did not provide unequivocal evidence of bacterial infection and did not provide assistance to any greater degree than the standard parameters of leukocyte count, protein, and glucose contents in the differential diagnosis of bacterial meningitis from that of any other etiology.

Adolescent↗

Extensive gas in tissues of the forearm after horsebite.

A 44-year-old man sustained lacerations of the forearm as a result of a horsebite. His arm became swollen after primary closure of the wounds, and a roentgenogram showed gas in the tissues of the forearm. Streptococcus anginosus and S mutans were isolated from the wounds.

Adult↗

Actinobacillus actinomycetemcomitans endocarditis.

Two patients had infective endocarditis due to Actinobacillus actinomycetemcomitans. One, a 52-year-old woman with a prosthetic aortic valve, was successfully treated with carbenicillin and gentamicin. The other, a 47-year old man with calcific aortic valve disease, required emergency valvectomy and prosthetic valve replacement and responded to a combination of penicillin and gentamicin.

Actinobacillus Infections↗