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Gastric cancer diagnostics has traditionally been histomorphological and primarily the domain of surgical pathologists. Although there is an increasing usage of molecular and genomic techniques for clinical diagnostics, there is an emerging field of personalised drug sensitivity testing. In this review, we describe the various personalised drug sensitivity testing platforms and discuss the challenges facing clinical adoption of these assays for gastric cancer.

The Cathra system is a commercial multipoint inoculation method for the identification of aerobic Gram negative bacteria. The system uses a replicator technique in which 21 different agar media can be inoculated simultaneously with 36 organisms. Identifications are made by use of a special computer database. The performance of this system was compared with that of the API 20E for the identification of 372 clinical isolates of Enterobacteriaceae and 133 miscellaneous Gram negative bacteria. For enterobacteria, the Cathra system was in 97% agreement with API 20E at species level and 98% at genus level. For miscellaneous Gram negative strains the two systems were in 59% agreement at species level and 77% at genus level. The Cathra system is suitable for use in diagnostic laboratories, especially those with a heavy workload and a wish to use break-point sensitivity testing. The identification database for miscellaneous Gram negative organisms, however, needs to be expanded.

The reliability of the bacitracin inhibition test to differentiate between 125 Lancefield group A and 122 non-group A beta-haemolytic streptococci was studied. Bacitracin discs containing 0-02, 0-04, or 0-1 international units and the conditions recommended by both the Association of Clinical Pathologists and the Federal Drug Administration for routine sensitivity testing were used. The results suggest that the presence or absence of a zone of inhibition around a 0-04 unit disc can be used routinely for the presumptive identification of group A streptococci and that a specific zone size can be used for reading the test only with a 0-1 unit disc.

A diffusion method for determining the sensitivity of pathogenic fungi to therapeutic agents is described using tablets containing the following antibiotics: amphotericin B, clotrimazole, econazole, fluorocytosine, and miconazole. The composition of the media used, standardisation of inocula, incubation time, and temperature are detailed.

A case of meningitis due to a group B streptococcus in a newborn baby is described. Treatment was successful; it depended upon the bacteriological diagnosis and sensitivity testing. Only a few such cases are reported in the British literature, but this type of infection may be more common than these reports would suggest.

Organisms of known susceptibility to antimicrobial drugs were distributed for sensitivity testing to laboratories participating in the United Kingdom National External Microbiological Quality Assessment Scheme. The results obtained were correlated with the methods used. Laboratories differed in their standards of antimicrobial drug sensitivity testing. An association between error rates and particular methods and practices enabled recommendations to be made on disc content, method of methicillin testing, preparation of inoculum, use of controls and use of lysed blood for sulphonamide testing. Some media appeared significantly better than others but because of the many factors involved further information is being sought to clarify this.

A technique was required for batch culturing and direct sensitivity testing of urine specimens to reduce increasing demands on laboratory services. A comparison was made between the filter paper strip method and multipoint inoculator technique using a Denley inoculator (Denley Ltd, Billingshurst, Sussex). The results showed that multipoint inoculation was a rapid, economical, and reliable method for the handling of large numbers of urine samples.