Читать книгу A Practical Approach to Special Care in Dentistry - Группа авторов - Страница 166

Tuberculosis is an infectious and transmissible disease caused by Mycobacterium tuberculosis, which is characterised by necrotising granulomatous inflammation that mainly affects the lungs (approximately 85% of cases). It is estimated that tuberculosis infects approximately 10 million individuals worldwide each year, 87% of which are concentrated in only 30 countries (predominantly countries with low economic levels). It is a notifiable disease in many parts of the world, with healthcare staff required to inform their health protection teams of a suspected/confirmed case.

Table 4.1.1 Considerations for dental management.

Risk assessment	Mycobacteria proliferate in the biofilms of dental unitsAlthough the risk of transmission is low, the transmission of tuberculosis in the dental clinic has been reportedPatients who start antituberculosis therapy are considered to not be infectious at 2 weeks, although negative sputum results might not start for up to 2 monthsPatients who have completed antituberculosis therapy generally have no risk of disease reactivationSide‐effects of tuberculosis medication:Especially in those older than 35 years, drug‐induced hepatitis can increase the tendency to bleedLeucopenia, thrombocytopenia and impaired vitamin K production (increasing bleeding risk) have also been describedA number of comorbidities can affect the delivery of dental treatment (alcoholism, drug addiction, hepatitis and HIV infection)
Criteria for referral	Latent tuberculosisThe patient is not infectious and can be treated in the dental clinic using standard infection control precautionsActive tuberculosisStandard precautions are insufficient to prevent bacterial transmissionUrgent dental treatment should be undertaken in a hospital setting with access to the appropriate personal protective equipment and ideally a negative pressure roomNon‐urgent treatment should be postponed for 3 monthsReferral to a specialised clinic or hospital centre is also determined by the patient's general condition (e.g. respiratory distress or concurrent advanced HIV infection)
Access/appointment	As routine, healthcare staff within the dental clinic should have tests for tuberculosis and evidence of immunity; this is evidenced by tuberculin skin testing or interferon gamma testing within the last 5 years, and/or checking of a BCG (cacillus Calmette–Guérin) scar by an occupational health professionalIf the patient has active tuberculosis, schedule the appointment for the last session of the day to minimise the risk of cross‐transmission; ensure there is access to filtering face pieces (FFP) – ideally FFP3 as these have the highest level of filtering capacityMinimise the number of staff in contact
Consent/capacity	Include any potential risks arising from the drugs used to treat tuberculosis and/or comorbidities
Anaesthesia/sedation	Local anaesthesiaNo specific recommendations; this is the method of choice to enable dental treatmentSedationAvoid sedation with nitrous oxide (risk of contamination)Consider the impact of respiratory depressionThe efficacy of diazepam can change in patients who are administered rifampicinAccelerated metabolism and reduced plasma concentrations of benzodiazepines have been notedGeneral anaesthesiaGeneral anaesthesia entails a risk of contamination, and some patients also have pulmonary function impairmentStreptomycin increases the activity of neuromuscular blockers (myasthenic syndrome)Where unavoidable, a plenum‐ventilated operating theatre should be used
Dental treatment	BeforeAny patient presenting with symptoms suggestive of active tuberculosis disease should be isolated, instructed to wear a surgical or procedure mask, and referred promptly for medical careFor those patients who require urgent dental treatment/who may be infectious, high‐efficiency particulate air (HEPA) filters, ultraviolet germicidal irradiation (UVGI) lamps and appropriate personal protective equipment should be available (FFP3)DuringThe use of sprays and the generation of aerosols (ultrasonic scaling equipment and high‐speed rotary instruments) should be reducedUse high‐volume suctionUse rubber damsUse facemasks with eye protection and change them if they get moistAfterSterilise the instruments with heat (mycobacteria are resistant to disinfectants)Ventilate the clinic after completing the session (open windows)
Drug prescription	Avoid paracetamol or recommend low doses (increased hepatic toxicity by rifampicin and isoniazid)It is prudent to avoid all drugs reliant on hepatic metabolismAvoid aspirin (increases the risk of ototoxicity by streptomycin, amikacin, kanamycin or capreomycin)Avoid clarithromycin and azole derivatives (they interact with rifampicin)
Education/prevention	All staff who provide dental care should undergo a Mantoux test when commencing employment, regardless of the setting's risk classification