An Unsatisfactory Pap Smear Followed by ASC-US in a District Hospital
A 29-year-old woman attends a district hospital for her first cervical cancer screening. She is HIV-negative, has one child and has no symptoms. A nurse takes a conventional Pap smear with a wooden spatula, spreads it thickly and fixes it after 30 seconds; the slide is labelled with a ward number only. In the laboratory, the slide is stained with Pap stain, but the smear is scanty, heavily blood-stained and more than 75% obscured by neutrophils. No liquid-based cytology or HPV testing is available. The report reads 'unsatisfactory for evaluation; repeat after treatment of infection.' The clinician asks whether to give antibiotics and repeat in five years. A repeat smear three months later is satisfactory and shows ASC-US.
1. Was 'unsatisfactory for evaluation' the correct interpretation? What are the adequacy criteria, and what should the laboratory recommend?
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Yes. Under the Bethesda System, a conventional smear should contain an estimated 8,000–12,000 well-visualised squamous cells (5,000 for liquid-based cytology). Obscuring blood or inflammation that covers more than 75% of epithelial cells makes a smear unsatisfactory. A transformation-zone or endocervical component is desirable but is not required for adequacy. This smear is scanty and heavily obscured, so it is unsatisfactory.
The recommendation should be to repeat in 2–4 months, not five years. Do not give antibiotics solely for 'inflammation' unless there is clinical cervicitis or a confirmed infection; treating inflammation does not reliably improve cytology and may delay screening. Correct the sampling technique: label with two patient identifiers, spread the material thinly, fix immediately, and sample the transformation zone. If the repeat is again unsatisfactory, refer for colposcopy.
2. The repeat smear shows ASC-US. How would you manage her in a setting without HPV testing, and what would change if she were 35 or HIV-positive?
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At age 29, reflex HPV testing is the preferred triage for ASC-US if available. Without HPV testing, repeat cytology in 1 year is acceptable; if the repeat is ASC-US or worse, proceed to colposcopy. Do not treat ASC-US with cryotherapy or antibiotics.
If she were 35 or older, HPV testing is preferred: HPV-positive → colposcopy; HPV-negative → return to routine screening. If she were HIV-positive, ASC-US warrants colposcopy regardless of HPV status because of the higher risk of high-grade disease. In a setting where visual inspection with acetic acid (VIA) is available, VIA is not a validated triage test for ASC-US and should not replace cytology or HPV follow-up. Document the plan and ensure a reliable recall system.
3. What quality problems contributed to the first report, and what corrective actions would you take in the laboratory and clinic?
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Quality problems included labelling with a ward number only, which risks a wrong-patient report; a thick smear; delayed fixation causing air-drying artefact; blood and neutrophils obscuring the cells; poor transformation-zone sampling; and an incorrect recommendation for five-year follow-up. The report also implied that infection should be treated before repeat cytology, which is not supported by the evidence.
Corrective actions: bedside labelling with two identifiers; training in smear preparation and immediate wet fixation; use of a spatula plus endocervical brush; staining and screening quality control; audit of unsatisfactory rates and cyto-histo correlation; a clear recall and result-communication system; and consideration of introducing HPV testing or liquid-based cytology. Reissue a corrected report with an explanation to the clinician and patient.