Brush cytology: an adjunct to diagnostic upper GI endoscopy

Cytopreparation of duodenal biopsy fixative improves detection rate of giardia in clinically suspected cases

INTRODUCTION

Giardia intestinalis is a flagellated protozoan, frequently documented as an agent for enteric illness worldwide. Laboratory procedures for diagnosis include stool examination, antigenic detection assays and, at times, mucosal biopsy. We hypothesised that the formalin fixative used as a preservative for mucosal biopsy can be a good diagnostic sample for detecting surface mucosal and luminal infective agents such as giardia. The aim of the study was to find out the utility of processing the remaining formalin fixative as a complementary diagnostic method for detecting giardia.

METHODS

This study included 200 cases of duodenal biopsies sampled over 6 months. The biopsies were picked up using clean forceps and the remaining fixative was processed using standard cytospin protocol. The cytospin preparation and formalin-fixed paraffin-embedded tissue sections were examined by two pathologists independently blinded to each others findings.

RESULTS

On cytology, trophozoites of giardia were detected in 23 out of 200 cases (11.50%). The cytomorphology of pear-shaped organism with paired flagella and nuclei is very diagnostic. One case also showed presence of cryptosporidium spores. No other intestinal parasite was seen. Out of the 23 positive cytology samples, only 12 (6%) corresponding formalin-fixed paraffin-embedded tissue sections showed presence of giardia.

CONCLUSION

Concurrent examination of duodenal biopsy and the formalin fixative cytopreparation in cases with high index of clinical suspicion of giardiasis proved to be a useful adjunct to biopsy diagnosis of giardiasis, which was statistically significant (P < .0001). This approach adds negligible cost and effort but with good diagnostic yield. We recommend that the formalin cytopreparation be used as a complementary technique to biopsy for cases suspected of intestinal parasitic infection.

Cytology Preparations of Formalin Fixative Aid Detection of Giardia in Duodenal Biopsy Samples

Giardiasis is the most common intestinal parasitic infection in the United States. The organism elicits no, or minimal, inflammatory changes in duodenal biopsy samples, so it can be easily overlooked. We performed this study to determine whether Giardia could be isolated from the formalin fixative of biopsy samples, and to evaluate the value of fluid analysis in the assessment for potential infection. We prospectively evaluated duodenal biopsy samples from 92 patients with a clinical suspicion of giardiasis or symptoms compatible with that diagnosis (ie, diarrhea, bloating, or abdominal pain) Biopsy samples were routinely processed and stained with hematoxylin and eosin. Histologic diagnoses included giardiasis (5 cases, 4%), normal findings (64 cases, 70%), peptic injury/active duodenitis (12 cases, 13%), and intraepithelial lymphocytosis with villous blunting (10 cases, 12%). Fifteen cases (13%) showed detached degenerated epithelial cells or mucus droplets in the intervillous space that resembled Giardia. Cytology slides were prepared from formalin in the biopsy container using the standard Cytospin protocol and reviewed by a cytopathologist blinded to the biopsy findings. Cytologic evaluation revealed Giardia spp. in all 5 biopsy-proven cases, and identified an additional case that was not detected by biopsy analysis. Organisms were significantly more numerous (mean: 400 trophozoites; range, 120 to 810) and showed better morphologic features in cytology preparations compared with tissue sections (mean: 129 trophozoites; range, 37 to 253 organisms; P=0.05). Our findings suggest that cytology preparations from formalin fixative can resolve diagnostically challenging cases and even enhance Giardia detection in some cases.

Greater than 95% success with 14-day bismuth quadruple anti- Helicobacter pylori therapy: a pilot study in US Hispanics

BACKGROUND

A combination capsule of bismuth, metronidazole, and tetracycline plus omeprazole given as 10-day therapy has an overall effectiveness of 92-93% in per-protocol analysis (Grade B) with eradication of 86-91% of metronidazole-resistant Helicobacter pylori. This study aimed to explore whether extending the duration to 14 days would improve overall effectiveness per protocol to ≥95% (Grade A) in a population in which metronidazole resistance was anticipated to exist.

METHODS

A one-arm, open-label pilot study of H. pylori-infected, asymptomatic/mildly dyspeptic adults, Hispanic residents of El Paso, Texas, received a 14-day course of omeprazole, plus the combination capsule. We cultured and Gram-stained specimens obtained using a minimally invasive orogastric brush. Helicobacter pylori status was determined by (13)C-urea breath test at 4 or more weeks post-therapy.

RESULTS

Forty-seven subjects (7 men and 40 women, average age 42 years) were entered. The per-protocol effectiveness was 97.1% (33/34) (95% mid-P CI: 86.3, 99.9); 100% of metronidazole-resistant strains were eradicated. Side effects were mild and self-limited but contributed to nonadherence. Therapy taken for <10 days was more likely to result in eradication failure (p < .001). Office-based orogastric brushing was well tolerated; positive cultures were obtained in 95%. Gram staining showed H. pylori-like forms in all specimens.

CONCLUSIONS

This pilot study supports the concept that 14-day OBMT therapy is likely to be more efficacious for H. pylori eradication (Grade A, PP basis) than a 10-day course where metronidazole resistance is suspected. If confirmed, 14 days should be recommended in populations where metronidazole resistance is common.