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Robert Hamilton

Publications and source records attributed to Robert Hamilton.

12 recordsLinked to original sources
PubMed2006

The relationship of rhinovirus-associated asthma hospitalizations with inhaled corticosteroids and smoking.

BACKGROUND: Although rhinovirus (RV) respiratory infections trigger asthma exacerbations, the etiologic association between this virus and severe exacerbations, as well as the clinical characteristics of adults at risk for RV-associated asthma that necessitates hospitalization, have not been established. METHODS: During 1999-2003, we conducted a cohort study of 101 adults prospectively enrolled at hospital admission for an asthma exacerbation. Patient characteristics and frequencies of RV in nasal specimens were analyzed, by reverse-transcription polymerase chain reaction (RT-PCR), at asthma-related hospital admission and at a 3-month convalescent follow-up visit. RESULTS: RV was detected by RT-PCR in 21% of hospitalized patients over a 4-year period and in 1.3% of patients who returned for a 3-month follow-up visit. RV detection was strongly associated with hospitalization for asthma (adjusted odds ratio [OR], 15.1 [95% confidence interval {CI}, 1.88-121.4]). After adjustment for baseline asthma severity, RV-positive patients were more likely than RV-negative patients to be current smokers and nonusers of inhaled corticosteroids (ICSs) (adjusted OR, 11.18 [95% CI, 2.37-52.81]; P=.002). CONCLUSIONS: RV respiratory infection is an etiologic agent in severe asthma exacerbations necessitating hospitalization in adults. Compared with hospitalized patients with asthma who were RV negative, RV-positive patients were significantly more likely to be smokers and nonusers of ICSs.

Adrenal Cortex Hormones↗
PubMed2006

Minimal change disease in association with fire coral (Millepora species) exposure.

Numerous agents have been associated with minimal change disease. We describe a previously unreported association in a 45-year-old white woman of scuba diving exposure to fire coral (Millepora species) that was followed by the development of nephrotic syndrome, acute renal failure, pulmonary edema, and intubation. The renal biopsy specimen was consistent with minimal change disease. Institution of corticosteroid therapy resulted in symptomatic improvement and resolution of proteinuria. Physicians, particularly those in scuba-diving areas, should consider minimal change disease in exposed patients with proteinuria because a prompt diagnostic and therapeutic approach may potentially limit complications.

Acute Kidney Injury↗
PubMed2005

Increased risk of complete congenital heart block in infants born to women with hypothyroidism and anti-Ro and/or anti-La antibodies.

OBJECTIVE: To determine whether the presence of hypothyroidism is associated with an increased incidence of neonatal lupus erythematosus (NLE) in infants of mothers with anti-Ro autoantibodies. METHODS: The cohort consisted of 87 women with anti-Ro antibodies who delivered 102 infants. All infants had a full history and physical examination within 12 weeks of birth, electrocardiogram (echocardiogram when clinically indicated), complete blood cell count with differential, liver function tests, and autoantibody profile. Nine women had hypothyroidism and 78 had normal thyroid function. RESULTS: At least one manifestation of NLE was seen in 7/9 (78%) infants born to mothers with hypothyroidism and 45/78 (58%) infants born to mothers with normal thyroid function. Complete congenital heart block (CCHB) was seen in 5/9 (55%) in the hypothyroid group and 10/78 (13%) of the normal thyroid function group (p < 0.005). Mothers with hypothyroidism had a 9-fold increased risk over women with normal thyroid function of having a child with CCHB (odds ratio 8.63). Twenty-seven (31%) of the women were healthy: 4/9 of the hypothyroid and 23/78 of the normal thyroid function group. Of the 23 infants born to healthy mothers with normal thyroid function, 15/23 (65%) had NLE and 8/23 (35%) of these had CCHB. CONCLUSION: Women with hypothyroidism and anti-Ro antibodies were at increased risk for delivering a child with CCHB compared to women with antibodies alone, irrespective of maternal health. This study indicates that women with hypothyroidism should be tested for anti-Ro antibodies, as they may be at risk to deliver a child with CCHB.

Adult↗
PubMed2005

Myocardial storage of chondroitin sulfate-containing moieties in Costello syndrome patients with severe hypertrophic cardiomyopathy.

Costello syndrome is a distinctive multiple congenital anomaly syndrome, characterized by loose soft skin with deep palmar and plantar creases, loose joints, distinctive coarse facial features, skeletal abnormalities, cardiac abnormalities (cardiovascular malformation (CVM), hypertrophic cardiomyopathy, tachycardia), predisposition to malignancy, developmental delays, and mental retardation. Previous studies with cultured fibroblasts from individuals with Costello syndrome demonstrate excessive accumulation of chondroitin sulfate-bearing proteoglycans, associated with both impaired formation of elastic fibers and an unusually high rate of cellular proliferation. Despite multiple clinical reports of cardiac abnormalities, there has been only one previously published report describing post-mortem findings in hearts from Costello syndrome patients. Here we provide a detailed description of the post-mortem findings of the hearts of three children with Costello syndrome. Routine histological examination and results of targeted histochemical and immunohistochemical studies revealed that in addition to cardiomyocyte hypertrophy, these hearts also demonstrated massive pericellular and intracellular accumulation of chondroitin sulfate-bearing proteoglycans and a marked reduction of elastic fibers. Normal stroma was replaced by multifocal collagenous fibrosis. Most peculiar was the finding that the bulk of the chondroitin sulfate accumulated in these Costello syndrome hearts is a chondroitin-6-sulfate. In contrast, deposition of chondroitin-4 sulfate was below the level detected in normal hearts. We propose that an imbalance in sulfation of chondroitin sulfate molecules and subsequent accumulation of chondroitin-6-sulfate in cardiomyocytes contribute to the development of the hypertrophic cardiomyopathy of Costello syndrome.

Abnormalities, Multiple↗
PubMed2004

Presentation, natural history, and outcome in children and adolescents with double orifice mitral valve.

Forty-six children, aged 2 days to 16 years (median 2.4 years) with double orifice mitral valve (DOMV), were studied. Partial atrioventricular septal defect was the most commonly associated cardiac lesion. Symptoms were related to the degree of mitral insufficiency and/or stenosis when present. Surgical intervention directed at DOMV was required in the minority of patients who underwent repair of associated cardiac lesions. The long-term morbidity attributable to DOMV was low.

Adolescent↗
PubMed2004

Making an impossible mission possible.

Cardiovascular disease (CVD) is widespread in developing countries. Hypertension is a major contributor of CVD. Left ventricular hypertrophy (LVH) is a risk marker in hypertensive populations. Identification of LVH and treatment of high-risk patients can result in more effective use of the limited resources. LVH is diagnosed by echocardiography, often unavailable in developing countries. In Gambia, we used a hand-carried ultrasound (HCU) to examine 1,997 people. Seventeen percent had hypertension; of these, LVH was found in 65%. The battery-powered HCU permits clinicians to detect LVH in areas with limited access to diagnostic equipment, allowing identification of a high-risk hypertensive population.

Adolescent↗
PubMed2003

In vivo sensitization to purified Hevea brasiliensis proteins in health care workers sensitized to natural rubber latex.

BACKGROUND: Thirteen proteins of natural rubber latex (Hevea brasiliensis) known to bind human IgE have been isolated and characterized as Hev b allergens. However, the in vivo importance of native Hev b allergens has not been defined in health care workers (HCWs) with natural rubber latex (NRL) allergy. OBJECTIVES: The principal aim of this study was to identify the major in vivo Hev b allergens in HCWs with NRL allergy confirmed by percutaneous sensitivity to nonammoniated latex (NAL). METHODS: Skin prick testing was performed with 7 (native) proteins purified from NAL (Hev b 1, 2, 3, 4, 6.01, 7.01, and a newly described Hev b 13) and recombinant Hev b 5 in 62 HCWs with histories of NRL allergy (group 1) confirmed by percutaneous reactivity to NAL and in 49 atopic HCWs without NRL allergy (group 2). Serial 10-fold concentrations of Hev b proteins (5 x 10(-5) microg/mL to 50 microg/mL) were tested; serum samples of subjects were assayed for serum specific IgE by immunoassays. RESULTS: Hev b 2, Hev b 5, Hev b 6.01, and Hev b 13 produced skin reactions in more than 60% of group 1 subjects, with Hev b 1, 3, 4, and 7.01 eliciting reactions in less than 50%. Only 1 of 49 group 2 workers reacted to a single Hev b antigen (Hev b 13). Specificity of 7 Hev b allergens was 100% and 98% for Hev b 13 in identifying workers with confirmed NRL allergy. Specific IgE by AlaSTAT and CAP immunoassays was elevated in 40 of 60 (67%) and 33 of 62 (53%) of NAL-reactive workers and produced false-positive test results in 4 of 49 (8%) and 3 of 48 (6%) group 2 subjects, respectively. CONCLUSION: Hev b 2, 5, and 6.01 are major in vivo allergens and Hev b 13 is a new major in vivo allergen among HCWs with allergy to NRL.

Adult↗
PubMed2003

Aortic dissection in children and young adults: diagnosis, patients at risk, and outcomes.

OBJECTIVE: To heighten the awareness of pediatricians and pediatric cardiologists to aortic dissection, a potentially dangerous medical condition. METHODS: We reviewed the charts of 13 patients, seen in four medical centers, who suffered acute or chronic aortic dissection over the period 1970 through 2000 whilst under the age of 25 years. RESULTS: There were seven male and six female patients, with the mean age at diagnosis being 12.1 years, with a range from one day to 25 years. Congenital cardiac defects were present in five patients, and Marfan syndrome in four. In three of the patients with congenital cardiac defects, aortic dissection developed as a complication of medical procedures. In three patients, dissection followed blunt trauma to the chest. We could not identify any risk factors in one patient. The presenting symptoms included chest pain in four patients, abdominal pain and signs of ischemic bowel in two, non-palpable femoral pulses in one, and obstruction of the superior caval vein in one. Angiography and magnetic resonance imaging were the main diagnostic tools. Overall mortality was 38%. Only six patients had successful surgical outcomes. CONCLUSION: Due to the rarity of aortic dissection a high index of suspicion is required to reach the diagnosis in a timely manner. It should be considered in young patients complaining of chest pain in association with Marfan syndrome, anomalies of the aortic valve and arch, and chest trauma.

Adult↗