PubMed Health⌕ Search

Biomedical subjects

C D Marchant

Publications and source records attributed to C D Marchant.

33 records · Page 2Linked to original sources
PubMed1987

Early recurrences of otitis media: reinfection or relapse?

In a prospective study, 36 (35%) of 103 patients had early recurrence of acute otitis media. We wished to identify risk factors for early recurrences (those recurring within 1 month of initial diagnosis) and to determine if the second episode was caused by the same pathogen (relapse) or a new organism (reinfection). When the same bacterial species was recovered in both episodes, Streptococcus pneumoniae were serotyped and Haemophilus influenzae were classified by biotypes and by electrophoretic pattern of the outer membrane proteins. Twenty-nine patients underwent tympanocentesis at the time of the recurrent episode. In 13, no pathogen was recovered either initially or at the time of recurrence. Twelve (75%) of the remaining 16 patients had reinfection; only four (25%) had relapse. Thus, early recurrences of acute otitis media were more often caused by a new organism. This finding suggests that underlying susceptibility to middle ear infection is important in the development of recurrent otitis media. Pediatricians should not assume that early recurrences are necessarily the result of failure of initial treatment. Tympanocentesis may be helpful in this setting to aid in choosing appropriate antibiotic therapy.

Acute Disease↗
PubMed1987

Serous and recurrent otitis media. Pharmacological or surgical management?

The management of recurrent acute otitis media and serous otitis media is both challenging and controversial. The efficacy of antimicrobial prophylaxis of children at high risk for recurrent acute otitis media is established, but the indications for such therapy are controversial. Tympanostomy tube insertion also decreases the frequency of recurrent otitis media. High-risk children can be successfully managed with chemoprophylaxis from autumn through to spring. If this fails, then tympanostomy tube insertion should be considered. Serous otitis media that follows acute otitis media resolves spontaneously in more than 90% of cases. Serous otitis media of unknown onset also has a strong tendency to resolve without treatment. Antihistamines and decongestants, although popular, have no significant effect on the course of serous otitis media. Antimicrobial therapy has a modest effect on the resolution of serous otitis media. Tympanostomy tubes usually improve the conductive hearing loss associated with serous otitis media and should be used when bilateral serous otitis media fails to resolve spontaneously. If repeated tympanostomy tube insertion fails, then adenoidectomy should be considered. With the course of management outlined, most children will have a successful outcome with conservative therapy and the need for surgery will be minimised.

Humans↗
PubMed1986

Objective diagnosis of otitis media in early infancy by tympanometry and ipsilateral acoustic reflex thresholds.

Otitis media in early infancy carries a high risk of recurrent otitis media and prolonged middle ear effusion. To fulfill the need for objective diagnostic methods in this age group, we investigated susceptance tympanograms and ipsilateral acoustic reflex thresholds in infants younger than 5 months of age. Tympanometry and acoustic reflex thresholds were performed with an otoadmittance meter using a 660 Hz probe tone. Tympanograms were interpreted using quantitative measures. These findings were compared with independent otoscopic diagnoses in 67 ears with middle ear effusion and 69 ears that were effusion free. Diagnoses were confirmed by tympanocentesis when clinically indicated. There was excellent agreement among otoscopy, peak tympanogram susceptance, and ipsilateral acoustic reflex thresholds (kappa 0.82 to 0.86, agreement 91% to 93%). We conclude that susceptance tympanograms and ipsilateral acoustic reflex thresholds are accurate diagnostic tests for otitis media in infants younger than 5 months of age.

Acoustic Impedance Tests↗
PubMed1986

A randomized controlled trial of amoxicillin plus clavulanate compared with cefaclor for treatment of acute otitis media.

We performed a randomized controlled trial of amoxicillin plus clavulanate versus cefaclor for treatment of acute otitis media. Total daily doses given in three divided doses were 40 mg/kg amoxicillin plus 10 mg/kg clavulanate, and 40 mg/kg cefaclor. Pathogens were eradicated from the middle ear exudate after 3 to 6 days of therapy in 35 (97%) of 36 patients given amoxicillin-clavulanate compared with 24 (75%) of 32 given cefaclor (P = 0.028). When analysis was restricted to patients with positive urine or serum drug assays during therapy, pathogens were eliminated in 33 (97%) of 34 patients given amoxicillin-clavulanate compared with 21 (75%) of 28 given cefaclor (P = 0.026). Bacterial isolates associated with bacteriologic failure of cefaclor therapy were Streptococcus pneumoniae (two patients), beta-lactamase-negative Haemophilus influenzae (four), and beta-lactamase-positive Branhamella catarrhalis (two). The single failure with amoxicillin-clavulanate therapy was associated with non-beta-lactamase-producing H. influenzae isolated from the middle ear exudate. We conclude that cefaclor is less efficacious than amoxicillin-clavulanate for the treatment of acute otitis media.

Acute Disease↗
PubMed1985

Bacterial etiology of conjunctivitis-otitis media syndrome.

Simultaneous cultures of conjunctivae and middle ear exudates were obtained from 20 episodes of the syndrome of purulent conjunctivitis and otitis media. Paired cultures from 18 episodes yielded Haemophilus influenzae at both sites. In two cases with prior topical antibacterial therapy of the conjunctivitis, H influenzae was isolated from the middle ear exudate only. Biotyping and outer membrane protein analysis of H influenzae isolates from five patients demonstrated that: conjunctival and middle ear strains were concordant in all cases, and all five patients had different strains. The conjunctivitis-otitis media syndrome is most often caused by strains of nontypable H influenzae of diverse clonotype.

Adolescent↗
PubMed1984

Do children with recurrent Haemophilus influenzae otitis media become infected with a new organism or reacquire the original strain?

Using the techniques of outer membrane protein gel analysis and biotyping, we characterized nontypable Haemophilus influenzae isolates from middle ear aspirates of 30 children with recurrent nontypable H, influenzae (NTHI) otitis media. Nine of the 13 children with early recurrence of NTHI otitis (less than 30-day intervals) had respective first and second isolates that were identical. In contrast, 14 of 18 children with late recurrences of NTHI otitis (greater than 30-day intervals) had respective first and second isolates that were different, whereas four children had late recurrences with organisms that appeared to be identical with their respective initial infecting strains. These results suggest that early recurrent NTHI otitis usually is a result of relapse with the initial infecting NTHI strain. In contrast, late recurrent disease is usually the result of infection with a new organism. However, the observation that four children had late recurrences with the original strains suggests that strain-specific protective immunity may not uniformly develop after recovery from NTHI otitis.

Child, Preschool↗
PubMed1984

A randomized controlled trial of cefaclor compared with trimethoprim-sulfamethoxazole for treatment of acute otitis media.

We performed a randomized controlled trial of cefaclor administered twice daily compared with trimethoprim-sulfamethoxazole (TMP-SMZ) administered twice daily for the treatment of acute otitis media. Pathogens were eradicated from the middle ear exudate after 3 to 6 days of therapy in 35 of 37 (95%) patients given TMP-SMZ compared with 28 of 40 (70%) given cefaclor (P = 0.017). Haemophilus influenzae was eliminated in 13 of 14 (93%) patients given TMP-SMZ compared with 10 of 18 (56%) given cefaclor (P = 0.047). Clinical outcomes failed to distinguish between patients given TMP-SMZ or cefaclor. Symptoms improved despite persistent infection in 11 of 13 (85%) patients; middle-ear effusion persisted after therapy in 38 of 61 (62%) patients despite eradication of pathogens. We conclude that twice daily TMP-SMZ is more efficacious than twice daily cefaclor for the treatment of acute otitis media and that clinical outcomes may fail to detect differences between antibacterial agents in comparative drug trials in acute otitis media.

Acute Disease↗
PubMed1984

Course and outcome of otitis media in early infancy: a prospective study.

We determined the course of otitis media in a prospective, longitudinal study of infants who were enrolled at birth and followed to age 1 year. Bilateral chronic otitis media with effusion developed in eight of 24 (33%) with onset of otitis media before age 2 months, compared to two of 30 (7%) with later onset (P = 0.012). Infants with bilateral chronic otitis media with effusion could be identified early: eight of 15 (53%) infants with bilateral middle ear effusion at age 2 months subsequently had bilateral chronic otitis media with effusion, compared to two of 55 (4%) infants without bilateral effusions at age 2 months (P = 0.000007). The onset of otitis media was symptomatic in 29 of 54 (54%), and asymptomatic in 25 of 54 (46%). If regular well-child examinations with otoscopy had not been performed in asymptomatic infants, bilateral chronic otitis media with effusion would not have been detected in six of 10 infants. Infants with otitis media in early infancy may be asymptomatic and are at high risk for chronic otitis media with effusion.

Age Factors↗
PubMedDate not supplied

Acute otitis media caused by Branhamella catarrhalis: biology and therapy.

Since 1980, we have observed an epidemic of otitis media caused by Branhamella catarrhalis. This event was characterized by studying the nasopharyngeal colonization of infants and children with B. catarrhalis and the clinical presentation and therapeutic outcome of acute otitis media caused by this organism. Pharyngeal colonization with B. catarrhalis was commoner in winter than summer. B. catarrhalis was present in middle-ear fluid (MEF) of 17% of children with otitis media, and was commoner in fall and winter (20%) than in spring and summer (11%, P less than .05). Seventy-five percent of isolates produced beta-lactamase (Ravasio type). In five of 20 patients, treatment with beta-lactamase-susceptible agents failed to sterilize B. catarrhalis-infected MEF. All of these five patients were infected with beta-lactamase-producing strains. The increasing prominence of antibiotic-resistant B. catarrhalis in acute otitis media may lead to a reevaluation of initial antibiotic therapy for acute otitis media, particularly in winter or in areas where colonization with such strains is prevalent.

Acute Disease↗
PubMedDate not supplied

Ipsilateral and contralateral acoustic reflexes in neonates.

Ipsilateral and contralateral acoustic reflexes were studied in neonates using 220 and 660 Hz probe tones and 500, 1000, 2000, and 4000 Hz activators. Activator sound pressure level was measured in all ears. Ipsilateral and contralateral reflexes were detected three times more frequently with a 660 Hz probe tone than with a 220 Hz probe tone. The maximum detection rate (76%) occurred with 1000 and 2000 Hz ipsilateral activators and the 660 probe tone. There was no significant difference between neonatal and adult ipsilateral thresholds at 500, 1000, and 4000 Hz. Neonatal intrameatal sound pressure levels for ipsilateral activators were found to be significantly higher than would be indicated from the otoadmittance meter manufacturer's specifications.

Acoustic Impedance Tests↗
PubMedDate not supplied

Emergence of beta-lactamase-producing strains of Branhamella catarrhalis as important agents of acute otitis media.

We performed a prospective study to monitor changes in the bacterial etiology of acute otitis media. Branhamella catarrhalis was isolated from middle ear exudates of 3 of 47 children (6.4%) studied between September 1979 and September 1980 and from 26 of 98 children (26.5%) studied between October 1980 and February 1982 (P = 0.0055). Twenty of 26 B. catarrhalis strains (76.9%) were found to be resistant to ampicillin and to produce beta-lactamase. In contrast only 2 of 26 strains of Haemophilus influenzae (7.7%) isolated from the same group of patients were resistant to ampicillin. We could not detect changes in culture methods, in demographic features, in patterns of medical care or in prior middle ear disease or antimicrobial drug usage, which might explain this striking increase in the relative importance of resistant strains of B. catarrhalis.

Ampicillin↗
PubMedDate not supplied

Identification of children requiring radiologic evaluation for urinary infection.

Sixty-nine children younger than 13 years of age with urinary tract infection were evaluated to identify risk factors for treatable urologic problems; i.e. those requiring surgery or prolonged antibiotic prophylaxis. All children had a renal ultrasound, intravenous pyelogram and voiding cystogram performed 4 to 6 weeks after the infection. Eleven children with treatable problems were identified, 10 with vesicoureteral reflux and 1 with a ureterocele. For identification of treatable problems the predictive value of a positive test was: (1) fever, 10 of 24 (41.7%); (2) abnormal D-deaminoarginine vasopressin renal concentrating ability, 8 of 24 (33.3%); (3) serum C-reactive protein greater than or equal to 1.0, 8 of 25 (32.0%); (4) Elevated urine N-acetylglucosaminidase, 5 of 16 (31.2%); (5) erythrocyte sedimentation rate greater than or equal to 25, 6 of 21 (28.6%); and (6) age less than 5 years, 10 of 43 (23.3%). Absence of fever denotes a low risk (less than 3%) of finding a treatable problem. Afebrile girls older than 5 years of age can have radiologic evaluation deferred until infection recurs. The presence of fever indicates a high risk of treatable urologic problems (41.7%) and warrants complete radiologic evaluation with the first urinary infection.

Child↗
PubMedDate not supplied

Ipsilateral acoustic reflexes in infants.

Ipsilateral acoustic reflex thresholds were studied in otoscopically normal ears of infants 2 weeks to 12 months old. Probe tones of 220 and 660 Hz and pure tone activators were used. Reflex recordings were free of activator artifact and were measured using quantitative standards. Reflexes were detected in 85% to 95% of infant ears for 500, 1,000, and 2,000 Hz activators but were present in only 76% of ears at 4,000 Hz. Median thresholds of 80 to 85 dB hearing level were obtained with all activators and both probe tones. There were no differences in proportions of reflexes obtained with the two probe tones. With a 500-Hz activator, thresholds at 220 Hz were lower than those at 660 Hz, while no threshold differences were demonstrated between probe tones at other activators. No relationship was demonstrated between age in the first year of life and presence or threshold of reflexes. Ipsilateral acoustic reflex measures have potential use in the identification of hearing loss and middle ear disease in infancy.

Adult↗