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P H Katelaris

Publications and source records attributed to P H Katelaris.

At least 19 recordsLinked to original sources
PubMed2005

The C-caffeine breath test distinguishes significant fibrosis in chronic hepatitis B and reflects response to lamivudine therapy.

BACKGROUND: The 13C-caffeine breath test is a non-invasive, quantitative test of liver function. AIM: To determine the utility of the 13C-caffeine breath test in chronic hepatitis B virus and its ability to monitor response to lamivudine. METHODS: Forty-eight chronic hepatitis B virus patients and 24 controls underwent the 13C-caffeine breath test. In 28 patients commenced on lamivudine, 13C-caffeine breath tests were performed at 1 week (n = 12) and after 1 year of therapy. RESULTS: Patients with Metavir F0-1 fibrosis (2.30 +/- 1.02 Delta per thousand per 100 mg caffeine) had a 13C-caffeine breath test similar to controls (2.31 +/- 0.85, P = 0.96). However, patients with F2-3 fibrosis (1.59 +/- 0.78, P = 0.047) and cirrhotic patients (0.99 +/- 0.33, P = 0.001) had a decreased 13C-caffeine breath test. Fibrosis correlated best with the 13C-caffeine breath test (r(s) = -0.62, P < 0.001). The 13C-caffeine breath test independently predicted significant (F > or = 2) and advanced (F > or = 3) fibrosis and yielded the greatest area under the receiver operating characteristic curve (0.91 +/- 0.04) for predicting advanced fibrosis. The 13C-caffeine breath test was unaltered by 1 week of lamivudine but improved by 61% (P < 0.001) in responders to long-term lamivudine, whereas in those with viraemia and elevated alanine aminotransferase, values remained stable or deteriorated. CONCLUSION: The 13C-caffeine breath test distinguishes chronic hepatitis B virus-related fibrosis and detects improvement in liver function in response to long-term lamivudine.

Adult↗
PubMed2004

Review article: oesophageal complications and consequences of persistent gastro-oesophageal reflux disease.

The major oesophageal complications associated with persistent gastro-oesophageal reflux disease (GERD) include erosive oesophagitis, ulceration, strictures and gastrointestinal (GI) bleeding. Although the causes of these complications are uncertain, studies indicate that erosive oesophagitis may progress to the development of ulcers, strictures and GI bleeding. Pharmacological treatment with proton pump inhibitors is favoured over that with H(2)-receptor antagonists for the treatment of strictures. The treatment of strictures is accomplished with dilation and many favour the concomitant use of proton pump inhibitors. Most gastroenterologists are seeing far fewer oesophageal strictures these days since the introduction of proton pump inhibitors. In addition, research has shown that oesophageal complications have a greater impact on patients suffering from night-time GERD than on those suffering from daytime GERD. Barrett's oesophagus is a significant complication associated with persistent GERD and those at risk generally experience a longer duration of symptoms, especially those with a high degree of severity. In addition, there is a strong relationship between Barrett's oesophagus and oesophageal adenocarcinoma. This is in part due to the association of obesity and the development of hiatal hernias. Furthermore, endoscopic screening is being used to detect Barrett's oesophagus and oesophageal adenocarcinoma in persons suffering from chronic GERD, even though screening may not have an impact on outcomes (Sharma P, McQuaid K, Dent J, et al. A critical review of the diagnosis and management of Barrett's esophagus: The AGA Chicago Workshop. Gastroenterology 2004; 127: 310-30.).

Adenocarcinoma↗
PubMed2003

Gastro-oesophageal reflux disease and Helicobacter pylori.

The interaction between gastro-oesophageal reflux disease (GERD) and Helicobacter pylori (H. pylori) infection has been the subject of intense scrutiny in recent years. Although the evidence base is incomplete it is now sufficient to clarify a number of key questions. H. pylori is not a risk factor for reflux disease. Similarly, H. pylori infection, in most patients, is not ''protective'' against the risk of developing reflux and oesophagitis. Furthermore, reflux and oesophagitis are not more likely to develop or to worsen after H. pylori eradication therapy and eradication does not make control of reflux symptoms with proton pump inhibitor (PPI) therapy more difficult. Long term PPI therapy in the presence of H. pylori infection does increase the rate at which gastric mucosal atrophy and intestinal metaplasia develop. Eradication therapy has been shown to reduce this risk. In the uninfected stomach, PPIs are associated with a low likelihood of these adverse histological changes. PPI therapy reduces the accuracy of diagnostic tests for H. pylori. The decision to test for and treat H. pylori infection in the context of reflux must be individualised based on patient factors including co-morbidity, age, gastric histology, family history and informed choice. Distinction must be made between treating symptoms and potentially reducing risks. A decision not to test for and treat H. pylori is now just as active a choice as is the decision to test and treat. Recent international consensus statements recommend eradication of H. pylori prior to long term PPI therapy in reflux disease, although there is not a universal agreement on this. Further research to clarify the risk and benefits of such an approach is required.

Journal Article↗
PubMed2001

Chest pain. Differentiating GIT from cardiac causes.

BACKGROUND: Chest pain is a common presenting symptom in general practice. Although a cardiac cause is not the commonest origin, a high index of suspicion is needed. When the diagnosis is not clear, a cardiac cause should be considered until proven otherwise. A gastrointestinal origin of chest pain is not infrequent and may be due to oesophageal, gastric or biliary disease. Oesophageal causes are most common and include reflux, hypersensitivity or dysmotility. OBJECTIVE: This paper reviews the main gastrointestinal causes that may present with acute chest pain. DISCUSSION: Clinical history taking is the key to decision making and guides the choice of prompt or routine investigation or a therapeutic trial. When reflux is suspected as the cause, a therapeutic trial of high dose antisecretory therapy is appropriate. Investigations may be helpful when typical reflux symptoms are not present or there is a poor response to this approach. Investigations may include endoscopy, ambulatory pH monitoring, barium swallow or oesophageal manometry.

Adult↗
PubMed2000

Randomized trial of omeprazole and metronidazole with amoxycillin or clarithromycin for Helicobacter pylori eradication, in a region of high primary metronidazole resistance: the HERO study.

BACKGROUND: The efficacy of omeprazole-based eradication therapies has been determined mostly in populations with low to moderate prevalence of metronidazole resistant Helicobacter pylori, yet resistance is high in many regions. AIM AND METHODS: The H. pylori eradication and duodenal ulcer healing rates after 1 week of either omeprazole 40 mg mane, amoxycillin 500 mg t.d.s. and metronidazole 400 mg t.d.s. (OAM) or omeprazole 20 mg b.d., metronidazole 400 mg b. d. and clarithromycin 250 mg b.d. (OMC) were compared in a randomized trial in Australia and New Zealand. Patients had a further 1 week of omeprazole 20 mg. Outcome was assessed at 6 weeks with stringent criteria (endoscopy, biopsies and 13C-urea breath test). RESULTS: Of 220 subjects randomized, the H. pylori eradication rates (all patients treated/per protocol) were 82%/85% for OMC and 58%/63% for OAM (P= 0.001). Pre-treatment metronidazole resistance was present in 56% and clarithromycin resistance in 6%. The eradication rate for primary metronidazole resistance isolates treated with OMC was 80% (CI: 65-90%) compared with 45% (CI: 29-62%) for OAM, whereas for sensitive organisms, the eradication rates were 94% (CI: 79-99%) and 79% (CI: 62-91%), respectively. Duodenal ulcer healing was 96% for OMC and 87% for OAM. Compliance was excellent and both treatments were well-tolerated. CONCLUSIONS: OMC is a well-tolerated, effective therapy for H. pylori eradication and duodenal ulcer healing in this region despite the high metronidazole resistance rate. OAM is less effective, largely due to the impact of metronidazole resistance.

Adolescent↗
PubMed2000

Aspartate aminotransferase: alanine aminotransferase ratio in chronic hepatitis C infection: is it a useful predictor of cirrhosis?

BACKGROUND: The clinical usefulness of the ratio of serum aspartate aminotransferase (AST) to alanine aminotransferase (ALT) has been explored in several liver disorders. It has been suggested that in patients with chronic hepatitis C virus (HCV) infection an AST:ALT > or = 1 has 100% specificity and positive predictive value in distinguishing cirrhotic from non-cirrhotic patients. Such statistical certainty attached to a simple biochemical test merits further evaluation. The present study, therefore, assessed the AST:ALT in patients with chronic HCV infection to determine the validity of the ratio in predicting cirrhosis and to correlate the ratio with the histological grade of necroinflammatory activity and fibrosis. METHODS: A retrospective analysis of 153 patients with chronic HCV infection was conducted. Serum biochemistry had been obtained within a mean of 4 weeks of liver biopsy. The histology was scored in terms of activity and fibrosis as described by Scheuer and correlated with AST:ALT. RESULTS: In 30 patients with cirrhosis, the mean AST:ALT (0.99 +/- 0.06) was higher than in 123 patients without cirrhosis (0.60 +/- 0.02; P < 0.001). A ratio > or = 1 had 95.9% specificity and 73.7% positive predictive value in distinguishing cirrhotic from non-cirrhotic patients, with a 46.7% sensitivity and 88.1% negative predictive value. The ratio also parallelled the Scheuer score with respect to fibrosis but not with respect to inflammation. CONCLUSION: Although relatively insensitive, an AST:ALT > or = 1 is highly specific but not diagnostic for the presence of cirrhosis in patients with chronic HCV infection. The ratio reflects the grade of fibrosis in these patients.

Adult↗
PubMed1999

The effect of dosing with omeprazole on the accuracy of the 13C-urea breath test in Helicobacter pylori-infected subjects.

BACKGROUND: The 13C-urea breath test (13C-UBT) is an accurate means of Helicobacter pylori diagnosis. However, proton pump inhibitors may suppress H. pylori and cause false negative results. AIM: To study the kinetics of H. pylori suppression by omeprazole during and after short-term use. METHODS: Volunteers underwent a baseline 13C-UBT (13C-urea 100 mg). H. pylori-positive subjects took omeprazole 20 mg daily for 14 days. Those who remained 13C-UBT positive (delta13CO2 >/= 5) continued omeprazole for a further 14 days. 13C-UBTs were performed weekly on omeprazole and then every second day after it was stopped. False negatives occurred when delta13CO2 fell to < 5. RESULTS: In 25 H. pylori-positive subjects (mean age 43.9 +/- 2.4 years; 21 females, 4 males) the mean baseline delta13CO2 was 28.1 +/- 3.4. False negative breath tests occurred in three subjects after 7 days of omeprazole and in a further four subjects after 14 days. A further six subjects developed negative tests between Days 14 and 28. Following cessation of omeprazole, the 13C-UBT became positive again in 12/13 subjects within 4 days and in all within 6 days, with a mean recovery to 99.9 +/- 18.6% of baseline delta13CO2. CONCLUSIONS: False negative 13C-UBTs are common during treatment with omeprazole and occur after as little as 7 days. Return to positive test results is rapid after cessation of omeprazole. These findings are relevant to the timing of testing in clinical practice.

Adult↗
PubMed1999

The impact of short-term ranitidine use on the precision of the 13C-urea breath test in subjects infected with Helicobacter pylori.

BACKGROUND: The 13C-urea breath test (13C-UBT) is a very accurate method of Helicobacter pylori diagnosis with a false-negative rate of 1-3%. However, the accuracy of the 13C-UBT is affected by potent acid inhibition with proton-pump inhibitors, which may suppress H. pylori and cause false-negative results. It is not known whether this occurs with less potent acid inhibition by H2-antagonists and any effect may be important clinically. OBJECTIVE: To determine the kinetics of 13CO2 excretion in H. pylori infected subjects during and after short-term ranitidine use. METHODS: Volunteers underwent a baseline 13C-UBT (positive: delta13CO2 > or = 5.0; negative: < or = 3.5; indeterminate: > 3.5 to < 5.0). Infected subjects took ranitidine 300 mg each evening for up to 28 days. 13C-UBTs were performed at weekly intervals and then every other day after ranitidine was ceased. If the 13C-UBT remained positive after 14 days, ranitidine was continued for a further 14 days. RESULTS: Thirty-one subjects were studied (mean age 40.4 +/- 2.1 years; 23 female/8 male; mean baseline delta13CO2 27.3 +/- 2.5). In 28 subjects the 13C-UBT remained positive during ranitidine use. The mean delta13CO2 rose to 124% (P< 0.06) and 121% (P < 0.05) of baseline at 14 and 28 days respectively. In two subjects, the delta13CO2 became indeterminate at day 7 (delta13CO2 4.3 and 3.8). In one of these, return to a positive value (delta13CO2 13.6; 103% of baseline) occurred while still on ranitidine. The other subject became positive again by day 3 off ranitidine (17.8; 119% of baseline). One subject had a transiently negative test after 21 days and this became positive again while still taking ranitidine. CONCLUSIONS: Ranitidine has a minimal effect on the 13C-UBT. The rate of indeterminate or false-negative tests is no greater than in patients on no anti-secretory medication.

Adult↗
PubMed1999

Treating Helicobacter pylori.

BACKGROUND: The treatment for Helicobacter pylori infection has changed continuously during the past decade and recommended treatments have not always been readily available in primary care. These factors have contributed to confusion and considerable variation in prescribing. OBJECTIVE: This short review outlines the key aspects of current treatment of H pylori. DISCUSSION: With the advent of single script, effective therapies, there should be more uniformity in treating this common infection. With appropriate choice of therapy and patient counselling to maximise compliance, excellent H pylori eradication rates are achievable in general practice.

Helicobacter Infections↗
PubMed1998

Prevalence and demographic determinants of metronidazole resistance by Helicobacter pylori in a large cosmopolitan cohort of Australian dyspeptic patients.

BACKGROUND: The pre-treatment sensitivity of Helicobacter pylori to metronidazole is a key determinant of successful eradication therapy and should influence local choice of therapy. However, there are few data defining the prevalence of metronidazole resistance (MR) in Australia. AIM: To determine prospectively the prevalence and demographic determinants of MR in H. pylori isolates from a large and cosmopolitan cohort of dyspeptic patients in Sydney. METHODS: Consecutive dyspeptic patients undergoing endoscopy had gastric biopsies for histology, urease test and culture. Metronidazole resistance was determined by E-test after subculture. An MIC > 8 micrograms/mL defined MR. Patient age, gender, birthplace and history of previous nitroimidazole use were recorded. RESULTS: In 732 patients, H. pylori was present in 46.4%. Culture was successful in 81% and subculture for MR in 88% of these. In 237 evaluable patients the overall MR rate was 59.1%. Five patients had had prior triple therapy for H. pylori (of which four of five had MR). Therefore, the primary MR rate in the study population was 58.6% (136/232). MR was more prevalent in younger patients (p = 0.0002). The MR rate was 70.4% in patients 18-39 years, 66.7% in those aged 40-59 years and lowest (38.9%) in those 60 years or older (p = 0.002). The MR rate was highest in patients born in Southeast Asia (72.8%, 59/81) and significantly higher than in Australian born (48.1%, 26/54), or Southern European (46.2%, 24/52) born patients (p = 0.002). There was no gender difference. Logistic regression to determine the impact of each variable (birthplace, age and gender) on MR identified Southeast Asia birthplace as a factor associated with greater likelihood of harbouring an MR isolate (OR 1.88, p = 0.02). Southern European born patients had the lowest risk of MR (OR 0.70, p = 0.02) as did patients older than 60 years (OR 0.56, p = 0.04). A definite history of prior metronidazole use was infrequent and not predictive of MR. CONCLUSIONS: While a high rate of MR is not unexpected in patients born in developing countries, the high rate in Australian born patients is surprising and of concern. This may relate to the high local usage of nitroimidazoles as monotherapy and has important implications for the effectiveness of metronidazole containing triple therapies.

Adolescent↗
PubMed1998

The relation between gastric vitamin C concentrations, mucosal histology, and CagA seropositivity in the human stomach.

BACKGROUND: Vitamin C may be protective against gastric cancer though infection with Helicobacter pylori is associated with a reduction in intragastric concentrations of vitamin C. AIMS: To examine the effects of H pylori infection, gastric juice pH, the severity and extent of gastric inflammation, and CagA antibody status of the individual on gastric juice and mucosal vitamin C concentrations. PATIENTS: One hundred and fifteen patients undergoing routine gastroscopy for investigation of dyspepsia. METHODS: High performance liquid chromatography was used to determine vitamin C concentrations. CagA antibody was detected by western blot analysis. RESULTS: Gastric juice ascorbic acid concentration was significantly lower in patients infected with H pylori compared with those uninfected (19.3 mumol/l (interquartile range (IQR) 10.7-44.5) versus 66.9 mumol/l (IQR 24.4-94.2), p = 0.003). The reduction in gastric juice ascorbic acid concentration was inversely related to the severity of gastritis (p = 0.01). CagA positive patients had significantly lower gastric juice ascorbic acid concentrations than CagA negative ones (14.8 mumol/1 (IQR 7.9-52.2) versus 39 mumol/l (IQR 19.9-142.2), p = 0.05). Decreased gastric juice dehydroascorbic acid concentrations were observed in patients with gastric atrophy and intestinal metaplasia. Mucosal ascorbic acid concentrations were also significantly lower in infected patients than uninfected patients (p = 0.04). CONCLUSIONS: The reduction in gastric vitamin C concentrations is related to gastric juice pH, the severity and extent of gastritis, the presence of H pylori, and the CagA antibody status of the individual. These findings may have implications in H pylori associated carcinogenesis.

Adult↗
PubMed1998

Idiopathic localized dilatation of the ileum. A rare cause of gastrointestinal haemorrhage in an adult.

A case of idiopathic localized dilatation of the ileum presenting in adulthood and associated with small bowel malrotation, ulceration and bleeding is described. To our knowledge, this is the first such report of this combination of features. The diagnosis was made using a small bowel barium study and intra-operative enteroscopy. Idiopathic localized dilatation of the ileum with ulceration should be considered as a rare small intestinal cause of occult or frank gastrointestinal blood loss in children or young adults.

Adult↗