Penny Lock: 42 years in microbiology

Penny Lock: 42 years in microbiology
10 June 2021
IBMS Fellow Penny Lock reflects on her career in the microbiology laboratory at Great Ormond Street Hospital


Since my career began in 1979, I have been fortunate enough to witness and participate in major changes and progress both in Biomedical Sciences and the Biomedical Scientist profession. When I first started at The Hospital for Sick Children (as Great Ormond Street Hospital (GOSH) was then called) it was a very different job and environment.

Our culture media was predominantly made in-house and only underwent rather crude quality control by today’s standards. We made a large selection of agar plates and assorted bottled broths used for enrichment and identification purposes. Reactions of organisms in individual sugar broths, decarboxylase broths, urea broths, Oxidation Fermentation tubes etc. were used in conjunction with textbooks such as Cowan and Steel and Bergey to identify organisms. Microscopy was used for looking at motility and various different staining techniques for capsules, metachromatic granules, spores etc. Then identification kits were developed such as the analytical profile index (API) and instead of remembering organism reactions, number profiles were remembered instead! Antigen/Antibody reactions were initially tested for by extracting antigens (for Streptococcal Lancefield grouping this required a boiling oil bath!) and a layering technique was used and a line of precipitation looked for. Then antibody coated latex particles were introduced and a new era began. Now of course MALDI-TOF and PCR techniques have revolutionised identification both in terms of speed of results and accuracy.

Back then, the laboratory wasn’t computerised. All specimens were given a number and details such as patient name, type and date of specimen were recorded by hand in a `day book’. Results were handwritten onto request forms which had carbon paper so a top copy could be sent back to the wards – and the bottom copy filed alphabetically in the huge banks of filing drawers. Computerisation began in 1984 with a system developed in-house. The first commercial system was introduced in 1988. It was only in the last two years that GOSH went completely paperless.

The laboratories used to be situated in the centre of the hospital between two wards. This meant that doctors would frequently drop in to ask about their patients’ results – and they liked to have a look at the cultures or at an interesting microscope slide. In 1996, a new purpose-built laboratory block was built adjacent to the hospital so this interaction more or less ceased. This aspect of the change was a shame, though Infectious Disease Registrars usually spend a day or two in the Microbiology Laboratory when they commence their rotation.

Blood cultures, a staple of any Microbiology Laboratory, were paired bottles. One contained broth and sloped agar, the other was to grow anaerobic organisms. The bottles were looked at macroscopically daily and sub-cultured using Pasteur pipettes after 24 hours, when a Gram stain was also made, and 7 days. Great care had to be taken not to introduce contamination during the sub-culturing process. In 1989, an automated Blood Culture analyser was introduced, initially requiring trays of bottles to be put through the analyser two to three times a day. Now continuous monitoring is normal and a positive blood culture is Gram Stained and has a Sepsityper performed to generally give a reportable initial identification within 30 – 60 minutes of flagging positive. Shifts are now worked at GOSH so this means the clinician is informed of a new positive blood culture any time of day or night so that appropriate treatment can be commenced immediately. The next step currently undergoing evaluation is to also be able to detect antibiotic resistance mechanisms at this early stage.

Antibiotic levels have also gone from being reported after 6 hours, when done by a bioassay, to a possible turnaround time of 15-20 minutes. Definitely an improvement for the patient but not so interesting to perform. I miss the days when your technological skills were really tested and if you had cut the wells on your plate accurately and loaded your controls neatly you were rewarded with a lovely straight line graph!

Cases of acute bacterial meningitis (such as Pneumococcal meningitis and Haemophilus influenza meningitis) were far more frequent prior to the vaccination programmes introduced in the 1980’s and 90’s - which dramatically reduced the incidence of these. Other organisms have emerged as pathogens which weren’t known about when I first started working. Patients with Cystic Fibrosis used to attend a mansion house called Tadworth Court in Surrey as a retreat for respiratory care. This wouldn’t be possible nowadays as the risk of them sharing multi-resistant Pseudomonas sp, Burkholderia sp, Non tuberculous Mycobacteria and fungi such as Exophiala dermatitidis is far too great!

Private patients from oversea areas such as the Middle East used to have an interesting array of parasites. However, this incidence is now greatly reduced and as a tertiary referral hospital it is rare for parasites to be detected.

The process of qualifying as a Biomedical Scientist has also changed a great deal. When I attended an interview to become a Junior B Medical Laboratory Scientific Officer (MLSO) I really knew very little about what the role involved (as was probably the case with the majority of interviewees). Now it is a graduate entry profession. I enrolled at Paddington College to do day release study for a Higher National Certificate (HNC) in Medical Laboratory Sciences (Junior A’s started at 16 years with O levels and did an Ordinary National Certificate followed by a HNC). Attending college for one long day and an additional evening whilst also working was very time consuming and quite tiring, but was also a great way to learn as you had the support of colleagues - and were also paid! It was also interesting meeting other students from hospitals all over London and the home-counties – and even further afield – and enabled the modern-day equivalent of networking. We would discuss our laboratories’ various methodologies and unlike today where methods tend to be standardised there was a fair degree of individualism which led to healthy arguing over whose methods were best!

Once the HNC was successfully achieved you became State Registered and it was also possible to further study for the Special Exam in your chosen field - which opened the doorway to possibly becoming a Senior MLSO. It was a tough exam with only approximately 60-65% of candidates being successful in any given year. The staff mix has changed since then. There used to be very few Medical Laboratory Assistants but now they form a substantial part of the workforce. Chiefs, Senior Chiefs and Principle Biomedical Scientists roles are now Higher Specialist Scientists and Laboratory Managers and seem fewer in number.

There were no external inspections to look at standards and no external quality assurance schemes. Now accreditation to ISO-15189 ensures that laboratories have effective Quality Management systems and maintain high standards, and Health and Safety inspections ensure safe practices are followed.

The last 15 to 18 months have, of course, been a very interesting time to have been working in a Microbiology laboratory, with a Global Pandemic being declared on March 11th 2020 caused by a novel Coronavirus, Sars-CoV-2. Just over a century before, the Spanish Flu Pandemic killed an estimated 50 million people. The only tools to fight that Pandemic were isolation, quarantine and disinfectants. There wasn’t a vaccine available, or antibiotics to treat secondary pneumonia. Scientific progress since those times has been absolutely enormous, and enabled this brand new virus to be sequenced, rapid diagnostic tests developed and a variety of different vaccines produced in record time. At GOSH diagnostic testing was up and running very quickly and we provided testing for some other Health Trusts as well in the early days of the Pandemic. The professionalism of my colleagues during this time was outstanding and everyone across the whole of Pathology collaborated to maintain the services despite the extra strain caused by new working practices introduced in order to keep safe. I am glad that I was still working and able to contribute during these challenging times. 

I wonder what changes are going to happen over the next 42 years. Technological advances will I am sure continue - particularly with molecular methodology and mass spectrometry. However, I do hope that microscopy, culturing and growing organisms never become obsolete. I will follow the progress of the profession with interest - whilst taking life at an easier pace!

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