The New Zealand General Practice Podcast

Clinical Snippets August 2023

Shownotes

Clinical Snippets August 2023

1.  Varicella and pregnancy

• Every effort should be made to confirm the diagnosis in the suspected positive contact and assess significance of exposure. Exposure or symptoms in the final two weeks of pregnancy should always be discussed with a specialist.  Exposure to varicella or zoster for which ZIG is indicated for susceptible persons includes: living in the same household as a person with active chickenpox or herpes zoster; face-to-face contact with a case of chickenpox for at least 5 minutes; close contact (eg, touching, hugging) with a person with active zoster.

• If immune status of the pregnant patient is uncertain check serology urgently.  NB In people with no history or recall of the rash, 70 to 90% are still found to be immune.  Immunosuppressed patients are susceptible to chickenpox at all times.  For pregnant women who are immunosuppressed and those with negative varicella serology,   IMAC recommends discussing the clinical circumstances with an infectious diseases physician before deciding on which course of action is best.

• If seronegative and exposure is ≤ 10 days earlier give Zoster Immune Globulin (ZIG) as soon as possible and if 7-10 days post exposure, give oral acyclovir or valaciclovir if the mother is at risk of varicella pneumonitis (is in the second half of pregnancy; has underlying lung disease; is immunocompromised; or is a smoker).  ZIG requires NZ Blood Transfusion approval to be dispensed. 

• If exposure is >10 days previously, closely observe for symptoms of varicella infection and treat promptly with acyclovir or valaciclovir if symptoms develop.  However,  if the mother is at risk of varicella pneumonitis and exposure occurred less than 14 days ago, treat with acyclovir of valaciclovir rather than waiting. 

• If a pregnant woman develops symptoms of chickenpox, treat urgently with antivirals and seek acute obstetric advice. Reduce antiviral dose in renal impairment.  Counsel pregnant women exposed to varicella about the risks of congenital varicella syndrome. The risk is highest in the first 20 weeks of pregnancy (0.4% in first 12 weeks, up to 2% in weeks 13-20).

• For further details including a great algorithm see the IMAC website.  The NZ Blood Transfusion Centre Handbook has details on ZIG.    

2.  I take a green one at night

A handy website for identifying medications is MEDLOOK where you can search a medication and get a photo (for most commonly used drugs) and written description of the tablet, capsule or tube (including generic versions). 

3.  Implicit bias

Issue 104 of the Maori Health Research Review includes findings from the New Zealand Health Survey which show that more than one in three Māori (37.6%) experience racial discrimination over their lifetime. This includes ethnically motivated personal attacks, as well as unfair treatment in healthcare, employment or housing. The proportion of Māori experiencing racial discrimination in the past 12 months increased from 10.8% in the 2011/2012 survey to 13.8% in the 2020/2021 survey, and was increased further when Māori women were analysed separately (9.7% to 16.8%). Verbal abuse was the most common type of racial discrimination in the 12 months before the 2020/2021 survey. Racial discrimination was associated with higher rates of psychological distress, lower rates of good to excellent self-rated health, and higher rates of unmet need for primary healthcare. The authors noted that data was based on self-reported experience, and that individuals may under-report episodes of racial discrimination.

The Ministry of Health has developed a range of resources as part of the  Ao Mai te Rā anti-racism Kaupapa.   This includes a video and podcast series to build collective understanding of the impacts of racism on health, while also exploring key levers in the health system that could be used for change.

Out of interest, you might want to consider taking a Harvard University Implicit Association Test which assesses for unconscious or implicit preference on a number of issues including skin tone, race, age and weight.  

4.  Ocular NSAIDs and corneal melting

• The June edition of Prescriber Update noted that in NZ more than 11,000 people per year are dispensed an ocular NSAID. A rare but potentially devastating side effect of ocular NSAIDs is corneal melting which can lead to corneal perforation and vision loss.

• Various conditions can cause corneal melting, including eye infections, sterile inflammation, certain medical conditions (such as rheumatoid arthritis), and surgical or chemical injury to the cornea. Use of ocular NSAIDs has recently been linked to corneal melting. However, the mechanism behind this association is unknown.

• Consider the possibility of corneal melting in patients using ocular NSAIDs who complain of blurred/distorted vision, worsening eye pain, eye irritation and hypersensitivity and/or ocular discharge. Check these patients for corneal damage.

• Certain situations may increase the risk for NSAID-induced corneal melting, including (list not exhaustive):

• frequent application and/or prolonged treatment duration
• concomitant use of corticosteroids
• concomitant conditions such as acute eye infections, rheumatoid arthritis, diabetes mellitus, ocular surface disease
• recent complicated ocular surgery or patients with repeat ocular surgeries within a short period of time.

• Advise patients to seek urgent medical attention if they experience signs/symptoms suggestive of corneal melting. Early diagnosis and treatment are critical to prevent further corneal damage.  Patients with evidence of corneal epithelial breakdown should immediately discontinue ocular NSAID treatment and be closely monitored. Due to the risk of corneal perforation and vision loss, patients with corneal melting are usually managed in a specialist setting. Management of corneal melting may involve medical and/or surgical intervention.

5.   Nasopharyngeal cancer (NPC)

• NPC is a rare undifferentiated form of SCC with variable rate of occurrence ( 1 case per 100,000 in European populations and up to 25-50 cases per 100,000 in Southern China).  There is a male preponderance and risk factors are genetic susceptibility, previous EBV infection, and environmental factors such as smoking, alcohol and nitrosamine containing foods. 

• Presenting symptoms are variable but include:

• Nasal symptoms (around 80%):  including unilateral nasal obstruction, epistaxis, post-nasal drip, hyponasal speech, or cacosmia.
• Otological symptoms (around 50%): secondary to Eustachian tube obstruction by the tumour, such as conductive hearing loss, middle ear effusion, or aural fullness. An adult with unilateral middle ear effusion requires visualization of the nasopharynx to exclude neoplasm.
• Neurological symptoms:  Cranial nerve palsy is found in 20% of nasopharyngeal carcinoma patients and may be the presenting symptom. The most commonly involved nerve is the abducens (VI) nerve (lateral rectus palsy – horizontal diplopia when looking to affected side)
• Nodal involvement: One of the most common presenting features is an enlarged cervical lymph node. Lymph nodes of the apex of the posterior triangle and the upper jugular are initially most commonly involved.  Supraclavicular nodes are the last to be involved and are a sign of advanced disease. 
• More information is available in a StatPearls publication. 

6.  Funded meningococcal vaccine

The lates IMAC update notes  youth justice facilities have been added as a ‘specified close-living provider’ to the funded criteria for both Meningococcal B and ACWY vaccines.  People aged between 13 and 25, in their first year living in boarding school hostels, tertiary education halls of residence, military barracks, or correctional facilities are eligible for free meningococcal B immunisation.  

A free catch-up programme is available until 28 February 2024 for all people aged 13-25 currently living in boarding schools, university hostels, military barracks, or correctional facilities.  See the Te Whatu Ora website for more details. 

7.  Family history of colorectal cancer screening update

Te Whatu Ora have released updated guidance on surveillance recommendations for individuals with a family history of CRC.  The main changes relate to incorporation of the NBSP. 

(i)  Category 1: slightly above-average risk of CRC: one first-degree relative diagnosed with colorectal cancer at or over the age of 55 years.

• Strongly advise these individuals to participate in the NBSP when they become eligible.
• Individuals should make healthy lifestyle choices3 and report any bowel symptoms to their health care provider.

(ii)  Category 2: moderately increased risk of CRC:  one first degree relative diagnosed under 55yrs or 2 first-degree relatives on the same side of the family diagnosed with CRC at any age (and no high-risk features from category 3). 

• Individuals have a colonoscopy every five years from age 50, or from an age 10 years before the earliest age at which colorectal cancer was diagnosed in the family/whānau, whichever comes first. 
• Provided they have had a high-quality colonoscopy within the previous five years, individuals then participate in the NBSP from the age of 60 years.  This includes Maori who are eligible to join the NBSP at age 50 years but will maintain colonoscopic surveillance and join at 60 yrs.
• If aged over 60 years and the previous surveillance colonoscopy documented polyps that require further colonoscopy surveillance, continue with this surveillance in line with the Update on Polyp Surveillance Guidelines 2020. When colonoscopy surveillance is no longer indicated, return these individuals to the NBSP.

(iii) Category 3:  potentially high risk of CRC:- refer to publication

• Refer individuals either to the New Zealand Familial GI Cancer Service (NZFGCS) or to a genetic service for an accurate risk assessment.
• Follow the colonoscopy surveillance plan advised by the NZFGCS, genetic service or bowel cancer specialist.

8.  Child and adolescent forearm fractures

Issue 218 of GP Research Review references a randomised trial in Australia comparing  ultrasonography or radiography for suspected pediatric distal forearm fractures.   Children and adolescents aged 5-15 years (n = 270) with an isolated distal forearm injury without visible deformity underwent either ultrasonography or radiography.  No clinically significant fractures were missed on ultrasound and there was no difference between the two groups in functional outcome after 4 weeks.  The reviewer noted the potential for use of POCUS for this purpose in rural general practice.