Thalassaemia and Haemoglobinopathies

• Thalassaemia is a reduction in globin chain production. Haemoglobinopathy implies
  production of an abnormal globin chain. Thalassaemia or haemoglobinopathy should be considered in an individual who has reduced or borderline red blood cell indices (MCV and /or MCH).
  

COVID PCR and respiratory virus PCR testing update

• There has recently been a sharp increase in cases of respiratory viruses, including COVID, Influenza A, RSV and others which are not possible to distinguish clinically.
• Consequently, where testing is indicated for management of symptomatic patients, it is important to request a respiratory viral PCR in addition to COVID PCR.

Syphilis

• Syphilis is an infectious disease of varied clinical presentations, often described as ‘the great imitator’. In recent years the rate has been increasing in Australia.

Faecal calprotectin (fCal)

• Faecal calprotectin (fCal) testing is now listed in the MBS for patients with undiagnosed gastrointestinal illness suspected for be IBS.

Thrombophilia

• Many tests are available to screen for hereditary and acquired thrombophilia.

Free Testosterone

• Steroid hormones are hydrophobic molecules and therefore highly bound to proteins in serum. It is generally accepted that only the small fraction of free steroid hormone is ‘active’ and taken up by the cell to exert its effect.

Prostate Specific Antigen (PSA)

• The main factor determining the serum PSA level is the age related growth of the prostate gland.
• Free and bound PSA forms reflect acute or chronic perturbations of the prostate.
• The rate of rise of PSA (doubling time) is a powerful prognostic indicator.

Vitamin B12

• Serum vitamin B12 testing remains the most common vitamin investigation in clinical practice and is included in the investigation of common problems such as anaemia and dementia.

Reference interval refinement - Are those results really abnormal?

• Reference intervals (previously termed normal ranges) should be specific to a patient’s age and sex and specific to the method used by that laboratory.

Which urine test?

• A spot urine with creatinine correction is the preferred method of urine collection rather than a 24 hour urine collection due to its ease and better reproducibility.

Anti-CCP

• Anti-CCP antibodies is more accurate than rheumatoid factor for the diagnosis of rheumatoid arthritis.
• Anti-CCP antibodies predict greater likelihood of future RA-related joint damage.

Respiratory Viruses, Mycoplasma Pneumoniae and Pertussis

• Improvements in swab technology enable the diagnosis of respiratory viruses and pertussis to be performed on a single nasopharyngeal swab.

Bleeding Disorders

• Investigation of a patient with a bleeding predisposition should follow a formula to prevent unnecessarily expensive, complex and time consuming testing, and to give the greatest opportunity for correct and early diagnosis without the need for repetitive testing. Investigation should only proceed after an adequate clinical history and examination.

Phi (Prostate health index)

• A new blood test for prostate cancer, the Prostate Health Index (phi) is now available through Melbourne Pathology.
• This new test has significantly improved accuracy in prostate cancer risk prediction over currently available tests. (Catalona et al, Journal of Urology 2011, see references)

Coeliac screening at Melbourne Pathology

• Serological screening for Coeliac disease relies on the detection of antibodies either of the IgA or IgG class.

Rh(D) Immunisation

• A great medical achievement of the last 50 years has been the introduction of preventative strategies for haemolytic disease of the newborn, in particular prophylaxis against Rh(D) immunisation.

Laboratory measurement of Serum Free Light Chains

• Serum free light chains (SFLC) can replace 24 hour urine electrophoresis and immunofixation in screening for monoclonal gammopathies.

Faecal Occult Blood (FOB) testing

• Contains information and instructions regarding FOB testing.

Molecular Karyotyping/Microarray Testing

• Microarray testing offers a significantly increased diagnostic return for individuals with indicated clinical phenotypes, compared to traditional karyotyping.
• This testing allows detection of duplications and deletions of 0.2Mb in size in comparison to traditional cytogenetics which has a typical resolution of 5 – 10Mb in blood specimens.

Listeriosis

• Listeriosis is a notifiable (Group B) disease. Notification must be sent in writing to the Victorian Department of Health within five days of diagnosis.

Neutropenia

• Neutrophil granulocytes are the most abundant leukocytes in humans.

Quantiferon TB Gold Assay

• The QuantiFERON TB^®  Gold Plus assay was developed in Australia primarily to detect Latent M.tuberculosis infection.

D-dimer in the diagnosis of venous thromboembolism

• Screening test – D-dimer is used as a screening test to rule out venous thromboembolism (VTE). It should not be used to confirm VTE, nor should it be used to exclude VTE in high risk patients.

Fasting for lipids/glucose

• As chylomicrons have ten times more triglyceride in them than cholesterol, fasting for less than 12 hours will result in triglyceride levels that are 50% to 250% higher.
• There is evidence that short fasting periods, for example after a large and late supper, may lead to elevated morning glucose levels.
• Similarly there is evidence that prolonged fasting, such as taking fasting glucose levels in the afternoon, will lead to half of the undiagnosed diabetics being missed.

Laboratory diagnosis of Measles

• The Department of Health requires suspected cases of Measles to be notified immediately without waiting for laboratory confirmation (1800 651 160).
• Measles is a highly contagious Group A notifiable infectious disease. Secondary infections occur in 75 – 90% of susceptible household contacts.
• Transmission of Measles virus is by respiratory droplets and direct contact with respiratory secretions.
• Serological testing and PCR are the mainstays of laboratory diagnosis.

Immunoserology – infectious mononucleosis

• Infectious mononucleosis (IM) is a syndrome most commonly caused by infection with Epstein-Barr virus (EBV), a member of the Herpes virus family.
• Approximately 50 percent of the population will be infected with EBV within the first decade of life, with the majority of later infections occurring from the age of 10 – 20 years. It is in this latter group that the IM syndrome is most often seen, though infections in other ages can occur.

Zika virus

• Zika virus has emerged in Brazil in association with an increase in reported cases of microcephaly among newborns. It has spread to many countries in Latin America and the Pacific region.
• At present, pregnant women and those planning pregnancy are advised to consider postponing travel to areas of Zika virus transmission

How to get the best out of an FNA

• The key to the success of the FNA consists of an adequate and representative cell sample and expertise in cytology.

The Australian modified Bethesda structured reporting for thyroid cytology

• FNA is the most reliable and cost effective diagnostic modality in the pre-operative assessment of the thyroid nodule in euthyroid patients. The key to the success of the FNA consists of an adequate and representative cell sample and expertise in cytology

Pathology collection tips and techniques

• A quality sample is achieved by correctly labelling and filling the tube fully, using optimal collection methods, centrifuging the sample when required, and avoiding haemolysis.

Antiphospholipid antibody testing

• The antiphospholipid (antibody) syndrome (APS) is characterised by vascular thromboses and foetal loss underpinned by procoagulant antiphospholipid autoantibodies.

Polycythaemia/Erythrocytosis

• An elevated haemoglobin or haematocrit is not an uncommon incidental finding on routine blood tests.
• It is most important to distinguish between primary polycythaemia and that which is secondary to another medical condition.

Biotin Snapshot

• High dose biotin intake may cause interference with laboratory test results

Laboratory investigation of gastrointestinal infections and infestations

• Melbourne Pathology is now offering in-house Faecal PCR testing.
• Acute infectious diarrhoea caused by most viruses, bacteria or parasites is generally self-limiting and doesn’t require specific antibiotics.

Safe transfusion practice for surgery

• A current Group & Screen means a fast response to blood demands and advanced notice of antibodies. Blood can be issued electronically within minutes.
• No current Group & Screen means a minimum delay of 50 minutes before the antibody screen is complete after the laboratory has received the specimen. If the antibody screen is negative, blood can then be issued by immediate electronic issue.
• No current Group & Screen and antibodies means selected blood must be obtained and a Crossmatch performed to prevent a haemolytic reaction. A delay of hours may result.

Vitamin D

• There are a large proportion of Melbournians who are vitamin D deficient which may be in some part due to the success of the Sun Smart message.

Making better rash decisions

• The best way to get better, more specific diagnoses from your skin pathologist is to provide them with a more complete clinical history when requesting histology.

Illustrating The Paris System for reporting urinary cytology

• The Paris System (TPS) is a standardised, comprehensive system for reporting urinary cytology. It was developed over several years and published in 2016 by a team of cytopathologists, surgical pathologists and urologists.
• It recognises the two distinct pathways of neoplastic transformation of urothelium, as well as cytology’s ability to reliably detect high grade urothelial neoplasia but not low grade urothelial neoplasia.

Improvements in our Thyroid Function Tests

• Melbourne Pathology returned to the Roche Elecsys platform in 2019 for free thyroid hormone measurement. Roche fT4 and fT3 offer us several performance advantages, but the most positive change you’ll see will be in our turnaround time, which will markedly improve.