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R F Straub

Publications and source records attributed to R F Straub.

18 recordsLinked to original sources
PubMed1996

Etiology of esophageal disease in human immunodeficiency virus-infected patients who fail antifungal therapy.

PURPOSE: To determine the etiologies of esophageal symptoms in human immunodeficiency virus (HIV)-infected patients failing antifungal treatment. METHODS: Between August 1, 1990 and December 31, 1994, all HIV-infected patients seen at a large inner-city hospital who had esophageal complaints despite being on antifungal therapy were prospectively evaluated for the cause of symptoms. Thus, the population studied included patients given empiric antifungal therapy for esophageal symptoms and patients who developed symptoms while on long-term antifungal therapy. Endoscopy was performed in all patients. The cause of symptoms was determined by the clinical, endoscopic, and pathologic findings, and follow-up after treatment. RESULTS: Over the 53-month study period, 74 patients failing empiric antifungal therapy were identified. The majority (77%) of these patients had esophageal ulcers; 25 patients had idiopathic ulcers and 24 had cytomegalovirus. In 2 patients, Candida was present with other causes of ulcerative esophagitis. Candida esophagitis alone was diagnosed in only 3 patients. No endoscopic abnormalities were observed in 14 patients (19%). An additional 24 patients developed esophageal symptoms while receiving antifungal therapy; endoscopic findings in these patients included ulceration in 16 (67%), Candida esophagitis alone in 2, and normal in 6. Empirically treated patients in whom odynophagia was not the only symptom, those with dysphagia alone, and those with a CD4 count > 100/mm3 were less likely to have an endoscopic diagnosis. CONCLUSIONS: Esophageal ulceration is the most common cause of esophageal symptoms in HIV-infected patients failing empiric antifungal therapy and those developing symptoms while receiving antifungal agents. Given these findings, endoscopy should be the test of choice for these nonresponders, rather than escalating the dose of antifungal agent, adding other empiric treatments, or performing barium esophagography.

Adult↗
PubMed1996

Prospective evaluation of biopsy number for the diagnosis of viral esophagitis in patients with HIV infection and esophageal ulcer.

BACKGROUND: Establishing a diagnosis of viral esophagitis in patients with human immunodeficiency virus (HIV) infection has important clinical relevance. However, the number of biopsies required to diagnose viral esophagitis is currently unknown. METHODS: Over a 34-month period, all HIV-infected patients with esophageal ulcer underwent 10 biopsies of the largest and/or most accessible lesion, primarily from the ulcer base. The first 3 specimens were placed in one formalin container, the second 3 in another, and 4 additional specimens in the third. Standard histopathologic methods were employed, as well as in situ hybridization or immunohistochemical studies in most patients, and viral cytopathic effect was defined using previously proposed criteria. Patients were then treated on the basis of the results of the initial biopsy specimens with both clinical and endoscopic follow-up. RESULTS: One hundred HIV-infected patients with esophageal ulcer were studied. Cytomegalovirus (CMV) was considered etiologic in 50 patients. Of these 50 patients, the first three biopsy specimens were sufficient to diagnosis CMV in 40 (80%). In 5 patients (10%), the first two sets were negative with only the third set of biopsies positive. Similarly, of the 4 patients with simultaneous CMV and herpes simplex virus (HSV) esophagitis, three sets of biopsy specimens were required for diagnosis of both agents in 3 patients. HSV esophagitis alone was found in 2 patients; diagnostic viral inclusions were present in the first 3 biopsies in each patient. Thirty-five patients had HIV-associated idiopathic esophageal ulcer; only one of these patients was misdiagnosed. CONCLUSIONS: At least 10 biopsies may be required to exclude viral esophagitis in HIV-infected patients. If biopsy specimens are adequate and no evidence of viral cytopathic effect has been found, the patient may be treated on the basis of the results of the initial clinical, endoscopic, and pathologic findings with close clinical follow-up rather than repeat endoscopy.

AIDS-Related Opportunistic Infections↗
PubMed1996

A prospective endoscopic evaluation of the causes of upper GI hemorrhage in alcoholics: a focus on alcoholic gastropathy.

OBJECTIVE: To determine prospectively the causes of upper GI hemorrhage (UGIH) in alcoholics, focusing on the prevalence of alcoholic gastropathy, and to compare the etiology of bleeding in patients who drink alcohol to that of nondrinkers. METHODS: From August 1, 1990 through September 9, 1994, all patients evaluated by the gastroenterology consultative service at a large inner-city hospital presenting with UGIH were prospectively identified. Patients had to have a subnormal hematocrit on or within 12 h of admission or a fall of at least 5 points from a previous baseline determination to be included. Upper GI endoscopy was performed in all patients within 48 h of admission. Alcohol use was quantitated as chronic (80 g or more per day for at least 1 month), binge, occasional, or none. RESULTS: Over the 4-yr study period, 727 patients met the inclusion criteria, and of these, 212 (29%) were classified as chronic alcohol users. Overall, peptic ulcer disease was the most common cause of bleeding (60%). Gastropathy (diffuse subepithelial hemorrhage) was considered etiological in only 32 patients (4%). The most common causes of gastropathy were portal hypertension in 22 patients and nonsteroidal anti-inflammatory drug use in five. Only three patients were identified in whom alcoholic gastropathy was considered etiological; in these patients, bleeding was mild and self-limited. When the causes of bleeding were compared between drinkers and nondrinkers, drinkers were more likely to bleed from varices (p = 0.024) or other portal hypertension-related causes (p < 0.01), whereas peptic ulcer was more common in nondrinkers compared with chronic users (67 vs 53%; p < 0.01). Esophagitis (p = 0.95) and Mallory-Weiss tear (p = 0.15) prevalences were not significantly different between the two groups. CONCLUSION: In the actively drinking patient, the most common causes of UGIH are peptic ulcer and disorders related to portal hypertension. Alcoholic gastropathy appears to be a rare and previously overemphasized cause of bleeding.

Adult↗
PubMed1995

Cytomegalovirus esophagitis in AIDS: a prospective evaluation of clinical response to ganciclovir therapy, relapse rate, and long-term outcome.

PURPOSE: Although cytomegalovirus (CMV) esophagitis is an important complication of acquired immunodeficiency syndrome, there has been little study specifically addressing the response to currently available antiviral therapy, relapse rate without maintenance therapy, and long-term outcome. PATIENTS AND METHODS: Over a 45-month period, 44 patients with CMV esophagitis established endoscopically and histopathologically were prospectively identified from among all human immunodeficiency virus (HIV)-infected patients undergoing endoscopy. Induction therapy consisted of intravenous ganciclovir at 10 mg/kg per day for approximately 14 days. Foscarnet was given at 60 mg/kg every 8 hours for nonresponders to ganciclovir. RESULTS: Of these patients, 35 completed induction ganciclovir therapy, resulting in a complete response in 17 (49%) and a partial response in 10 (29%), yielding a 77% overall response rate. Seven of 8 nonresponders were subsequently treated with foscarnet, with a clinical response seen in 5 patients. In the 18 eventual complete responders to ganciclovir or foscarnet followed up without maintenance therapy, 7 (39%) relapsed at a median of 4 months (range 2 to 18 months). In all cases, relapse was manifested by recurrent odynophagia. Reinduction ganciclovir therapy yielded a complete response in 1 patient and a partial response in 2, and induction foscarnet treatment resulted in a complete response in the other treated patients. During long-term follow-up, 1 complete responder developed CMV colitis with concurrent retinitis, and 4 other patients developed retinitis. The median survival after diagnosis was 8.2 months, although survival for greater than 1 year was seen in 4 patients. No patient died as a direct result of esophageal disease, although ulcer-related bleeding may have contributed to death in 2 patients with end-stage liver diseases and hepatic encephalopathy. CONCLUSIONS: CMV esophagitis has a favorable response to induction ganciclovir therapy, and a long-term remission may occur after induction therapy alone. Despite the favorable response to ganciclovir therapy, the long-term survival is poor, reflecting the severe immunodeficiency of these patients.

AIDS-Related Opportunistic Infections↗
PubMed1995

Prospective evaluation of oropharyngeal findings in human immunodeficiency virus-infected patients with esophageal ulceration.

OBJECTIVE: Although the presence of oropharyngeal (OP) candidiasis plays an important role in the evaluation of human immunodeficiency virus (HIV)-infected patients with esophageal symptoms, there is little information on the utility of OP findings in patients with esophageal ulceration. METHODS: Over a 54-month period, all HIV-infected patients with esophageal ulceration had careful inspection of the oropharynx at the time of presentation with esophageal complaints and at endoscopy. HIV-infected patients without esophageal ulceration undergoing endoscopy during the last 30 months had OP findings similarly documented. OP ulceration ulceration was determined based on clinical, endoscopic, and histopathological findings. RESULTS: Of the 124 patients identified with esophageal ulcer, 14 (11%) had coexistent OP ulceration: herpes simplex virus, four; idiopathic esophageal ulcer, four; cytomegalovirus, three; herpes simplex virus and cytomegalovirus, two; idiopathic and cytomegalovirus, one. Four patients had OP ulcer without esophageal ulcer; only one of these patients had esophageal symptoms. All OP lesions healed with therapy for the esophageal ulcer. Twenty-eight patients with esophageal ulcer had OP candidiasis (23%); 21 of these patients (75%) also had Candida esophagitis. The sensitivity and specificity of OP ulcer for esophageal ulcer were 11% and 97%, respectively. The positive and negative predictive values of OP candidiasis for esophageal candidiasis were 90% and 82%, respectively. CONCLUSIONS: OP ulceration is uncommon in patients with esophageal ulceration, with the exception of herpes simplex virus esophagitis. OP candidiasis is common in patients with underlying esophageal ulcer, potentially resulting in diagnostic confusion. OP candidiasis appears to be a moderately useful diagnostic marker for Candida esophagitis.

AIDS-Related Opportunistic Infections↗
PubMed1994

Variable endoscopic appearance of colonic lymphoid tissue.

The variable appearance of gut-associated lymphoid tissue at videocolonoscopy has not been well documented. Over a 3-year period all patients undergoing high resolution videcolonoscopy underwent biopsy of any identified abnormalities for correlating histopathologic findings with endoscopic appearance. We identified several distinct patterns for lymphoid tissue: small well-circumscribed nodules, red rings, large coalescing vesicles with or without central pits, or white plaques. A mass-like appearance of the ileocecal valve was present in one patient. Although individually each of these patterns appeared characteristic, overall, variability appeared dependent on the colonic location and underlying disease. Prominent lymphoid tissue was most frequently seen in patients with underlying disorders resulting in stimulation of the immune system. We take this to mean that there is a broader spectrum of colonic lymphoid tissue as assessed by videocolonoscopy than previously appreciated. The variability of these normal structures has potential diagnostic implications.

Adult↗
PubMed1993

Determination of penicillin G, ampicillin, amoxicillin, cloxacillin and cephapirin by high-performance liquid chromatography-electrospray mass spectrometry.

This report contributes to a preliminary investigation of high-performance liquid chromatographic (HPLC)-mass spectrometric (MS) methods for confirming beta-lactam antibiotic residues in bovine milk. Initial work for each antibiotic evaluated the collisional activated dissociation (CAD) spectra that could be generated between the capillary and skimmer in the electrospray (ESP) interface. The drugs show various characteristic fragmentation, mostly within the beta-lactam ring and the amide group. Response for a particular compound in a given solvent can vary drastically. Usually, the more organic component in the solvent, the higher the ESP response. In many cases use of acetonitrile also results in slightly better ion currents than for methanol when comparing equal percentages of either organic solvent in water. The ESP response of most of the tested antibiotics can be enhanced by the addition of formic acid or acetic acid to the mobile phase methanol-water (1:1). In general, the negative ion spectra are lower in intensity, exhibiting an [M-H]- ion and producing less fragmentation at higher CAD voltages as compared to positive ion spectra. An isocratic reversed-phase HPLC method for the separation of a mixture of five common beta-lactam antibiotics was developed using acetic acid as a mobile phase additive and optimized for detection with a new ESP HPLC-MS interface. A post-column split ratio of 70:1 for the eluent from a 150 x 2 mm I.D. column was chosen to provide the required lower flow-rate (approximately 4 microliters/min). The limit of detection for the simultaneous determination of these antibiotics was estimated to be 100 ppb. Electrospray HPLC-MS could be used to confirm these antibiotics for quantities down to about 100 pg entering the mass spectrometer. Multiresidue analysis with microbore HPLC-ESP-MS has the advantage that no post-column splitting of the eluent is required and all of the analyte (on-column injected) will be transferred into the ESP interface. Preliminary work showed good mass spectrometric sensitivity down to the level of regulatory interest, but chromatographic separation efficiency must be improved.

Amoxicillin↗
PubMed1993

The liver-spleen scan in systemic amyloidosis: a clue to the diagnosis.

The clinical findings in cirrhosis and systemic amyloidosis may be similar, leading to difficulties in diagnosis. We studied three patients with systemic amyloidosis with a 99mTc sulfur colloid liver-spleen scan. In all three patients, uptake by the spleen was less than the liver, in contrast with the increased splenic uptake seen in patients with cirrhosis. The liver-spleen scan may be a useful tool in differentiating patients with cirrhosis from those with systemic amyloidosis when clinical findings fail to give the proper diagnosis.

Aged↗
PubMed1993

Biodistribution of Sn-117m(4+)DTPA for palliative therapy of painful osseous metastases.

Tin-117 has certain physical characteristics (half-life of 13.6 days, low-energy-conversion electrons, gamma photon of 158.6 keV) that suggest that it may be a favorable agent for radionuclide therapy. It has been shown in animal models that Sn-117m in the chemical form Sn(4+)diethylenetriaminepentaacetic acid localizes selectively in bone. The authors therefore studied its whole-body distribution in 10 patients to obtain absorbed dose estimates for therapy. The results showed that more than 50% of the administered activity was absorbed in the bones of patients with metastatic carcinoma. Retention was determined primarily by radioactive decay. For adult men, the radiation absorbed dose estimate averaged 54.8 mGy/MBq (203 rad/mCi) to bone surfaces and 6.1 mGy/MBq (22.6 rad/mCi) to the red marrow. All other tissues received less than 1/10 of the dose received by red marrow. These results suggest that a clinical therapeutic trial should be attempted.

Adult↗
PubMed1993

Re: In search of CMV.

Explore the source record for details and available documents.

AIDS-Related Opportunistic Infections↗
PubMed1990

Blood cell labeling with 99mTc: progress and perspectives.

Blood cell labeling with 99mTc has progressed through various developmental phases. In the case of red cell labeling, the science seems to have matured sufficiently, although minor refinements in the procedures will no doubt continue to be made. During the last 3 to 5 years, there has been a resurgence of interest in labeling leukocytes and platelets with 99mTc. As a result of these efforts, the techniques for these cell types appear to be developing slowly, having finally come out of their infancy. Progress in these directions over the last 3 1/2 years is summarized and discussed in this article. Emerging techniques that offer the promise of combining simplicity and convenience with reliable and reproducible data are highlighted. Mechanisms involved in the various labeling approaches, if studied and understood, are included. Recent efforts on cell labeling with 99mTc using the monoclonal antibody approach are summarized. Although results in this area are quite preliminary, the monoclonal antibody approach holds the greatest promise for labeling leukocytes and platelets in vivo, and thus overcoming the biggest drawback of current techniques, ie, cell separation and handling before labeling. This is a US government work. There are no restrictions on its use.

Animals↗
PubMed1990

Recent developments in blood cell labeling research.

A number of recent developments in research on blood cell labeling techniques are presented. The discussion relates to three specific areas: 1) A new in vitro method for red blood cell labeling with 99mTc, 2) a method for labeling leukocytes and platelets with 99mTc, and 3) the use of monoclonal antibody technique for platelet labeling. The advantages and the pitfalls are examined in the light of available mechanistic information. Problems that remain to be resolved are reviewed. An assessment is made of the progress as well as prospects in blood cell labeling methodology including that using the monoclonal antibody approach.

Animals↗
PubMedDate not supplied

Prospective endoscopic characterization of cytomegalovirus esophagitis in AIDS.

Cytomegalovirus (CMV) esophagitis is an important cause of esophageal ulceration in patients with the acquired immunodeficiency syndrome. However, the endoscopic appearance of these lesions has not been well characterized. During a 3-year period, we identified 141 CMV esophageal ulcerations endoscopically in 33 patients. CMV esophagitis was the index diagnosis of human immunodeficiency virus (HIV) infection in 8 patients. Odynophagia was almost uniformly present, although gastrointestinal bleeding was the initial manifestation in 5 patients. Multiple ulcers were identified in 58% of patients. Giant ulcers were seen in 28%, whereas 43% of the lesions were less than 1 cm in greatest dimension. The majority of the lesions were located in the middle to distal section of the esophagus. The ulcers were characterized as either shallow or of intermediate depth in 74% of patients; deep ulcers were seen in 8%; diffuse erosive disease was found in 6%; and the ulcers had a "heaped up" appearance in 12%. In contrast to reports from previous studies, CMV esophageal disease appeared highly variable endoscopically. Multiple, well-circumscribed ulcerations were the most common endoscopic findings, although lesions could vary in number, size, and appearance. As this lack of uniformity may cause CMV esophagitis to be confused with other conditions characterized by esophageal ulceration, all HIV-infected patients with esophageal ulceration should undergo endoscopy with biopsy so that a definitive diagnosis can be obtained.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

Simultaneous multiresidue analysis of beta-lactam antibiotics in bovine milk by liquid chromatography with ultraviolet detection and confirmation by electrospray mass spectrometry.

A multiresidue analytical method was developed for the simultaneous determination of amoxicillin, cephapirin, procaine penicillin G, ampicillin, cloxacillin, and ceftiofur in bovine milk. The method involved ultrafiltration of milk diluted with an equal volume of 50% acetonitrile through a 10,000 dalton molecular mass cutoff filter. Separation of these beta-lactam antibiotics from other milk components was performed by ion-paired (octane- and dodecanesulfonate) liquid chromatography using a phenyl column eluted with acetonitrile-water solution. Ultraviolet absorbance of the column effluent was monitored in the 200-350 nm range of a photodiode-array detector. For quantitation, the chromatograms were acquired at lambda 210 nm for penicillin G, ampicillin, and cloxacillin; lambda 230 nm for amoxicillin; and lambda 290 for cephapirin, procaine, and ceftiofur. The limit of detection for the simultaneous determination of these antibiotics was estimated to be 100 ppb. Liquid chromatography/electrospray mass spectrometry could be used to confirm these antibiotics for quantities down to 100 pg entering the mass spectrometer.

Animals↗