February 2022

Clinical Snippets February 2022

1.  Peripheral artery disease and walking

From a recent Tools for Practice:  In patients with PAD, exercise therapy improves maximum walking distance and pain-free walking distance by up to ~200 meters over 2 to 78 weeks compared to usual care. No benefit has been demonstrated for amputation or mortality. The most commonly studied exercise is supervised walking 2-3 times per week for 30-60 minutes, although other supervised activities (example resistance training) may be beneficial in those who cannot tolerate walking.

• Patient understanding of physical activity for PAD should be explored:
• 63% identified walking as the primary aetiology for their pain, 90% thought walking would worsen symptoms.

2.  Electronic communication and the internet

Last year MCNZ released an updated statement on Use of the internet and electronic communication  which includes the following points (and I recommend reviewing the whole document):

• Inappropriate communication, including use of social media, can be considered unprofessional, whether this is directly related to a doctor’s work or not.
• Patients who get information from the internet may wish to discuss this with you. You should use this as an opportunity to talk about how sometimes the information obtained from these sources may be of poor quality, incorrect, or create unrealistic expectations. Provide sound reasons for the views you express and, where possible, provide documentation, to support the alternative advice or treatment that you are recommending.
• There are security issues specific to the use of email. It is difficult to verify a person’s identity from an email; some families and groups share a common email address; and computers (particularly family computers) may be accessed by a number of different people. For these reasons, check with the patient before sending them sensitive information by email.

3.  Aotearoa New Zealand STI Management Guidelines – Chlamydia

• There is growing evidence that sexually transmitted Chlamydia trachomatis establishes a persistent rectal reservoir that is refractory to treatment with azithromycin stat.
• The evidence is very strong for men who have sex with men, but is growing for women too.
• Contemporary guidelines are abandoning azithromycin stat and reverting to doxycycline 100mg BD for seven days with stat azithromycin only if doxycycline contraindicated or patient is highly likely to be non-adherent.
• Symptomatic anorectal infection generally requires specialist advice as further testing and management is complex

4.  Recurrent Bacterial Vaginosis (BV)

A recent article in NZ Doctor includes the following key points on recurrent BV:

• There have been no major advances in the treatment and cure of bacterial vaginosis, perhaps because the pathophysiology is complex, multifactorial and not fully understood.
• Standard therapy is seven days of twice-daily metronidazole, but many women are looking for alternative treatments that may provide longer duration between recurrences.
• Intravaginal boric acid capsules have been used historically and may be considered an alternative, though unfunded, treatment to use in conjunction with antibiotic therapy.

DermnetNZ lists a number of alternative treatments including gels to reduce vaginal pH and a vaginal antiseptic dequalinium.  It does not appear any of the recommended products are in NZF but Aci-Jel is available OTC (around $30 per 100g tube).    Boric acid vaginal pessaries can be bought on-line – eg pHD $199 for 72 caps (about five courses)

A 2009 Cochrane review concluded that research at that time research did not provide conclusive evidence that probiotics are superior to or enhance the effectiveness of antibiotics in the treatment of BV.  However, a 2019 meta-analysis concluded that probiotic regimes are safe and may exhibit a short-term and long-term beneficial effect for BV treatment.  There are many OTC preparations available.  Probiotics do not form part of HealthPathways or Aotearoa New Zealand STI Management Guidelines recommendations for management of BV. 

DermnetNZ also discusses cytolytic vaginosis as a cause of possible of persistent vaginal discharge.  This is the result of a hyperacidic vaginal environment due to overgrowth of lactic acid producing bacilli, with management aiming to reduce vaginal pH (baking soda douching). 

5.  Extended use of intrauterine devices

Tools for Practice examined the evidence around effectiveness of intrauterine devices for prevention of pregnancy when used beyond the manufacturer recommended use period.  The conclusion was:

If it is not possible or desirable to replace a levonorgestrel 52mg or copper-T380A intrauterine device (IUD) at the end of the approved duration of use, small observational studies demonstrated similar efficacy and safety for up to two additional years, with little evidence afterwards. Guidelines suggest that with patient-informed discussion, deferral of IUD replacement for up to twelve months is reasonable.

6.  Antipsychotic switching tool

A useful tool is available from NPS Australia that assists prescribers when changing a patient’s antipsychotic treatment. Using the interactive tool, the prescriber enters the formulation (oral or depot), the current medicine the patient is prescribed and the medicine they want to switch the patient to. This then generates prescribing information about how to stop one medicine and start the next, along with key clinical issues to be aware of. All antipsychotic medicines currently funded in New Zealand are included in the tool.

7.  Serotonin syndrome – a reminder

A relatively common prescribing complaint I see relates to patients concerned they were not warned of the risk of serotonin syndrome, or that they experienced serotonin syndrome, usually secondary to co-prescribing of two serotonergic agents.  The most common combinations I see are tramadol and SSRI, SNRI or TCA, or when a TCA is added to an existing antidepressant regime.  A 2015 communication from Medsafe discusses the issue in more detail and is worth a quick review.