A Practical Guide to a Safe Sequence of Donning and Doffing of Personal Protective Equipment in Relation to COVID-19

When caring for patients with suspected or confirmed COVID-19 (coronavirus disease 2019), especially when involved in procedures that generate aerosol, personal protective equipment (PPE) with full-body coverage is recommended. The Centers for Disease Control and Prevention emphasizes and recommends the following principles with regard to donning and doffing of PPE: (1) training and education (rigorous and repeated training of the health care workers [HCWs]), (2) all HCWs must exhibit competency in the PPE donning and doffing, and (3) PPE doffing should be done in a manner that prevents self-contamination or self-inoculation with contaminated PPE or hands (remove the most contaminated PPE items first, perform hand hygiene at each stage of doffing, and discard disposable items in containers for biomedical waste).

Should we test TPMT enzyme levels before starting azathioprine?

Thiopurine methyltransferase (TPMT) is the main enzyme responsible for inactivating toxic products of azathioprine (AZA) metabolism. Patients with homozygous deficiency of this enzyme have no enzyme activity and ideally should not be given AZA. Patients with heterozygous deficiency have 50% of enzyme activity and have been shown to respond well and tolerate half a standard dose. We describe a patient with homozygous deficiency of TPMT who developed life threatening neutropenic sepsis, and advocate that all patients should be tested for TPMT activity prior to starting AZA therapy.

Role of anaesthetic equipment in transmitting nosocomial infection

There is a potential risk of bacterial and viral infection being transmitted through anaesthesia circuits. Several studies have shown contamination of parts of anaesthetic equipment with bacteria that colonise the mouth and upper airway. A definite relationship between such contaminated anaesthetic equipment and subsequent lung infection remains to be established. Various factors contribute to the transmission and pathogenesis. Among the recommendations for preventing transmission of infection through anaesthetic circuits are using a bacterial/viral filter for every patient or using disposable circuits. Owing to financial constraints, all these recommendations may not be practical in India. Possible guidelines for India may include discarding endotracheal tubes after single use and rigorous cleaning and disinfection of masks and laryngoscopes. Corrugated tubings used in the expiratory limb of the circuit may be washed with soap and water after each patient and dried before use. It is advisable to disinfect all such tubings in 2% glutaraldehyde, and then to wash in water and to dry before use at least once a day or when they are visibly contaminated.

Should health care workers in the tropics be immunized against varicella?

In tropical regions, chickenpox affects both adults and children. Therefore, healthcare workers in the tropics are vulnerable to hospital-acquired varicella infection and they may transmit infection to susceptible hospitalized individuals. Although the varicella vaccine is safe and effective, its cost is a deterrent to its use in routine immunization programmes. In order to assess whether vaccination of susceptible healthcare workers to prevent hospital-acquired transmission may be justified, we have documented the frequency of varicella among healthcare workers in our hospital. There were 96 admissions for varicella during the 1993-1997 period; staff and student nurses accounted for 76%. The peak season of admission was from February to April. The attack rate in staff and student nurses was 0.78 and 1.54 per 100 person-years, respectively. While community outbreaks of varicella occur in this region once in 4-5 years, hospital outbreaks of varicella occurred every year. This poses the risk of transmission to hospitalized patients, with serious consequences among immunocompromized individuals. Therefore, we recommend systematic selective vaccination of susceptible healthcare workers to break this cycle of annual varicella outbreaks among hospital personnel.

A study on clinical profile of falciparum malaria in a tertiary care hospital in south India

Malaria continues to be a major problem in tropical countries. To study the clinical features and complications of malaria in a tertiary care hospital in south India, records of 183 patients were analysed. Among 86 patients with P. falciparum and mixed infection, 24 (28 per cent) had cerebral malaria and 32 (37 per cent) had hyperbilirubinemia. Twenty-three out of 32 (72 per cent) patients with jaundice had direct hyperbilirubinemia and elevated liver enzymes suggesting hepatocellular damage. Mortality of the order of 10 per cent was seen only in P. falciparum malaria. High incidence of hepatic involvement and hepatorenal failure were the unusual features observed in the study.

Typing of Acinetobacter baumannii isolated from hospital-acquired respiratory infections in a tertiary care centre in southern India

In an attempt to define the epidemiology of Acinetobacter baumannii infection, 27 isolates, obtained from hospital-acquired respiratory infections, were typed using random amplified polymorphic DNA (RAPD) profile and antimicrobial susceptibility patterns. Ten different patterns were obtained with ERIC2 primer: 14 isolates had a similar profile representing a single strain. Within RAPD types, isolates could be further classified based on their antibiogram; however, strains of different types had similar antibiograms. This study showed that many different genetic types of A. baumannii are prevalent in our hospital. While antibiograms alone are not sufficiently discriminatory, RAPD typing helps in identifying outbreaks and in assessing infection control procedures within a hospital.

Impact of introduction of sharps containers and of education programmes on the pattern of needle stick injuries in a tertiary care centre in India

Documentation of needlestick injuries was started in the Christian Medical College Hospital, Vellore in 1993. In 1995 large sharps containers were introduced, accompanied by an intensive education programme. Details of documented injuries from 1993 to 1999 were analysed using the Epi-Info software. A total of 347 injuries occurred, mainly due to improper disposal of needles, re-capping and carelessness during use. The percentage of injuries attributed to disposal fell from 69.2% in 1995 to 38.5% in 1996 (after the education programme). A further decrease was noted after the additional introduction of small sharps containers. In 1995, 73% of injuries involved housekeeping staff, this fell to 12% in 1998. Relatively simple interventions decreased the numbers of injuries, and we recommend that all healthcare institutions should have a system of documenting needlestick injuries, and take measures to decrease their incidence.

Clinical manifestations and survival pattern of Wilson's disease

BACKGROUND

Wilson's disease usually presents in childhood. Early recognition and treatment is crucial to retard the progression of this disease, which can be debilitating, if not fatal. We analysed the clinical manifestations and survival pattern of patients admitted at our centre from 1993 to 1996.

METHODS

Hospital records of patients were reviewed to obtain the clinical manifestations. The survival status of patients was determined by a prospective follow up. The Kaplan-Meier survival curve and univariate Cox proportional hazards model were used to determine the survival pattern and risk for death in Wilson's disease.

RESULTS

A total of 60 patients were studied. The median age at onset of symptoms was 12 years (range 5-52 years). The log rank test showed a significant difference in the mean (SD) survival between patients who presented with hepatic [87.36 (15.26) months] and neurological symptoms [114.33 (9.14) months]. Cox proportional hazards analysis showed a hazard ratio of 4.9 for patients with a hepatic presentation compared to those with neurological presentation.

CONCLUSION

The presentation of Wilson's disease is not limited to the paediatric age group. Patients with a hepatic presentation had a five-fold higher risk of mortality when compared to those with a neurological presentation.

Preventing transmission of blood-borne pathogens to health care workers

Health care workers are exposed to blood-borne pathogens, mainly the human immunodeficiency virus, hepatitis B virus and hepatitis C virus. Infection by these viruses leads to chronic or fatal illnesses which are expensive and difficult to treat. Individuals who harbour these viruses may be asymptomatic and hence all patients should be assumed to harbour a blood-borne pathogen. All health care workers should take adequate precautions (a set of guidelines termed 'universal precautions'). Methods of preventing transmission of blood-borne pathogens include vaccination against hepatitis B virus, following universal precautions and taking adequate post-exposure prophylaxis.