What is a type iv latex allergy

The participation rate was adequate, with 79% answering the questionnaires. The sample was not obtained by random selection, however, but depended on participants returning questionnaires. As a result, generalisability to the hospital may not be possible.

Among the 59 participants who met the inclusion criteria (symptoms due to using latex gloves), 12/45 (%) tested positive for latex sensitisation by ImmunoCAP or SPT. The findings are comparable to those of studies conducted at Dr George Mukhari Hospital (Pretoria) (22%)9 and Groote Schuur Hospital (Cape Town) (%).6

Our latex allergy prevalence of % is higher than the % at the Dr George Mukhari Hospital, which is our sister hospital.9 This difference can partly be explained by the fact that in the latter study only the ImmunoCAP test was performed, with no SPT follow-up.

We calculated our prevalence with only the ImmunoCAP without an SPT result in the participants with negative blood tests and found a prevalence of % (7/), similar to that of the Dr George Mukhari study.

The prevalence of latex allergy at other SA teaching hospitals and institutions has been reported as: Groote Schuur Hospital (Cape Town) %, Red Cross War Memorial Children&#x;s Hospital (Cape Town) 5%, Tygerberg Hospital (Parow, Cape Town) % and the South African Institute of Medical Research, now the National Health Laboratory Service (Johannesburg), % Our prevalence of % is comparable to most of these, with only Tygerberg Hospital demonstrating a higher prevalence of %.

The actual prevalence of latex sensitisation may be higher than these figures propose, because some studies show that 25% of SPT-positive patients may be asymptomatic

Rates of latex sensitisation and allergic reactions own increased in HCWs exposed to NRL since the s, with prevalences of — 17% reported,12 A study on primary prevention of NRL allergy in Germany by Allmers et al. has confirmed a positive correlation between the use of powdered NRL gloves and suspected occupational latex allergy There is recent evidence that rates of NRL allergy own fallen significantly as a result of latex-free environment strategies and use of low-allergen, powder-free gloves in some industrialised countries.3 Termination of exposure to NRL products is an accepted means of secondary prevention in latex-sensitised individuals

The commonest presenting symptoms in both latex-positive and -negative participants who met the inclusion criteria were nasal (% and %, respectively), followed by asthma in latex-positive (%) and contact dermatitis in latex-negative subjects (%).

Other symptom profiles did not reveal any significant differences between latex-positive and -negative participants.

What is a type iv latex allergy

There was no statistically significant difference in symptoms between the latex-sensitised and non-sensitised participants, except in those who presented with dermatitis. This can be explained by the fact that the k82 ImmunoCAP does not test some Hev b allergens such as Hev b , Hev b 12 and Hev b SPTs may be negative even in people who are sensitised or allergic to latex, as sensitivity has been shown to be 93 — 96%

Shortcomings of the study

Greater participation, especially by doctors, would own improved the power and generalisability of the study.

Several participants only had blood testing performed without follow-up SPTs, which could own influenced the prevalence, as some might own tested positive by SPT.

Recommendations

NRL allergy has been shown to be an significant cause of occupational disease. It is significant to increase awareness of the sensitising and disease-causing effect of latex gloves in HCWs. Powdered gloves may cause serious latex allergy problems because the latex proteins adhere to the powder, become airborne and are subsequently inhaled This can cause sensitisation in atopic individuals.

Powdered latex gloves can be a hazard not only to the wearer but also to other people in the workstation.

What is a type iv latex allergy

The importance of creating latex-free workplaces cannot be over-emphasised, as evidenced by one of our participants who developed anaphylaxis requiring mechanical ventilation. In an ideal situation latex-free gloves should be used, especially in high-exposure areas. This is not feasible in most settings, however, because of the high cost of these gloves It is therefore recommended that powder-free, low-allergen gloves be used as a preventive measure because of their ability to decrease sensitisation Individuals who are sensitised to latex should avoid direct contact with latex gloves but can work at the station with other workers provided the latter are using powder-free gloves.

Once an individual is sensitised it is hard to prevent the emergence of symptoms, especially systemic reactions on contact with latex Everyone with proven latex allergy should wear a Medic Alert bracelet or band to assist HCWs avoid using latex-containing products such as urinary catheters, endotracheal tubes, oxygen facemasks and laryngeal airways when caring for them.


Etiology

Individuals in health care, including physicians, nurses, and dentists and those who work with chemicals or in labs, wear gloves more frequently than the general public.

Numerous medical items contain latex besides gloves and include:

  1. Tourniquets

  2. Drainage tubes

  3. Stethoscopes

  4. Syringes

  5. Catheters

  6. IV tubing

  7. Dental dams

  8. Electrode pads

  9. Respirators

  10. Condoms

This increased exposure to latex puts them at risk for sensitization initially and ultimately, a latex allergy if sensitization continues. Direct exposure to the allergen through the use of gloves, condoms, or catheters is the most common cause of latex allergy with a direct correlation of sensitization to the quantity of exposure.[8] Proteinscan be transferred from gloves to the skin directly or can contaminate food from food handlers, resulting in a reaction in those who are already sensitized.[10] Aside from direct exposure to the allergen, individuals with certain food allergies are at higher risk of latex reactions.

Allergies to unused fruits and vegetables such as avocado, banana, chestnut, kiwi, celery, and pear cause patients to own a higher likelihood of hypersensitivity to latex. Those with latex allergy also own a higher sensitivity to those fruits and vegetables.[8][2][9]

Airborne particles are another source of allergen exposure as latex can be inhaled into the lungs.

What is a type iv latex allergy

Cornstarch particles in latex gloves and tire dust are the most common sources of inhaled particles resulting in latex reactions.[8]


Epidemiology

There own been varying reports of the prevalence of latex allergy among the general population.Latex allergy affects 1 to 2 percent of the population, and one study showed that latex sensitization is more likely in health-care workers exposed to latex compared to the general population. Clinical manifestation, however, was approximately the same in both health-care workers and the general population.[4] In developing countries, there are more cases of latex allergy, as more latex products are in use.[10][2] Latex results in the most common cause of contact urticaria in occupational health as well as the second most common cause of intraoperative anaphylaxis, second to muscle relaxants.[10]

Epidemiologic studies own shown that a specific patient population such as those with spina bifida are at increased risk of developing a latex allergy with the prevalence of spina bifida hypersensitivity ranging from 20% to 65%.[2][8][10] The hypersensitivity is likely related to latex exposure from numerous corrective surgeries and procedures.[4] Patients with repeated catheterization due to urological abnormalities are also at increased risk.[8]


Material and methods

Development and logistics

We conducted a small-scale pilot study of 10 participants in January to test our questionnaire.

We then started our study by having a discussion on latex allergy in every workstation in order to explain the study and answer questions. Questionnaires and information on latex allergy were given to HCWs who wanted to participate in the study. We collected blood from participants who met the inclusion criteria and later did skin-prick tests (SPTs) in those whose blood tests were negative.

Specific IgE measurements

The k82 Latex ImmunoCAP system (Phadia, Uppsala, Sweden) was used to determine serum-specific IgE to latex antigens. The latex allergen components documented on this system are Hev b 1, Hev b 2, Hev b 3, Hev b 5 Hev b , Hev b , Hev b , Hev b Hev b 8, Hev b 9, Hev b 10 and Hev b The first 7 latex allergens listed above are of medium to high significance, with Hev b through Hev b 11 having low significance in HCWs and children with spina bifida.8 There is cross-reactivity, especially to bananas, avocados and kiwi fruit, with Hev b through Hev b Hev b 8 to Hev b 11 reveal low cross-reactivity with some fruit and mould allergens.8 A worth of > kU/l was considered positive.

Clotted blood was collected and sent to Lancet Laboratory, Polokwane, for testing.

Study population

A cross-sectional descriptive study was conducted among HCWs (nurses, medical doctors and cleaners) working in high-risk areas of Mankweng Hospital. The grand majority of HCWs at highest risk of latex sensitisation are nurses. Ethics clearance was obtained from the Ethics Committee of the University of Limpopo, Polokwane Campus. The participants signed forms indicating their informed consent to participate in the study.

Participants were recruited during March — December from the intensive care unit, labour ward, gynaecology and postnatal ward, casualty, outpatient department, neonatal intensive care unit, antenatal clinic, operating theatre, central sterilising department, radiology, high care, and the Thuthuzela Rape Clinic.

The hospital has a nursing staff complement of and has a policy of keeping nurses in their preferred workstations permanently. Every participants had been in their workstation for a year or more. The number of nurses in diverse stations is shown in Table 1.

Questionnaire

A self-istered questionnaire was designed to elicit any allergic symptoms, collecting the following information: (i) demographic data; (ii) symptoms; (iii) family history; (iv) food allergy (avocados, bananas, carrots, pineapples and watermelons); (v) previous allergy evaluation and therapy; (vi) hospitalisation; and (vii) surgery. The questionnaire was in English, the official language used to record patient information at the hospital.

What is a type iv latex allergy

HCWs in diverse workstations were addressed to explain the study, and questions asked were clarified. They were addressed in English, Sepedi, Tshivenda and Xitsonga, the four common languages spoken at the hospital. For the few participants who could not understand English well, the information was interpreted in their home language by the investigators, who can speak every three African languages. There is evidence that a questionnaire addressing past symptoms of latex allergy can be useful in screening for latex allergy.7 Questionnaires are particularly useful in the identification of sensitised and asymptomatic patients belonging to high-risk groups and in prevalence studies.5

Participants were required to score their symptoms after exposure to latex as absent, mild, moderate or severe and to state whether they were work-related or not.

Symptoms were graded as severe if the participant had needed medical attention or admission to hospital.

Inclusion criteria for further study (latex sensitisation and allergy testing) were: (i) confirmed or suspected latex allergy; (ii) severe reaction after exposure to latex; (iii) allergy to food that cross-reacts with latex; (iv) any other symptom with work-related deterioration; (v) 1 or more severe symptoms listed in the questionnaire; (vi) 2 or more moderate symptoms in the questionnaire; and (vii) 4 or more mild symptoms in the questionnaire. Fifty-nine participants met these inclusion criteria for latex sensitisation and allergy testing.

Sample size

We assumed the prevalence of type 1 latex allergy in the study population to be about 10%, with a margin of error of 4%.

In order to be 95% confident we needed to own a entire of HCWs in high-risk areas using simple random sampling.

Skin-prick tests

SPTs were performed on subjects who tested negative to blood tests. We used standardised 1 mm-tipped lancets (ALK-Abello, Madrid, Spain) and latex extracts ( µg/ml protein concentrate). Histamine (10 mg/ml) was used as a positive control and normal saline as a negative control (ALK-Abello). A drop of the extract was placed on the volar area of the forearm and introduced into the epidermis through lancet puncture.

The result was examined after 15 minutes and the average diameter of the wheal measured. A positive result was interpreted as an average diameter of &#x;3 mm compared with the negative control.


Conclusion

The prevalence of latex allergy in HCWs at Mankweng Hospital is significant, and represents a serious occupational disease. It is significant to strive for a latex-free working environment for HCWs, especially atopic workers. Risk risk of latex allergy could be minimised by decreasing extractable proteins in latex products.

This may reduce the risk of litigation against the hospital and Department of Health.

References

    Accepted 18 February

    Introduction

    Latex comes from a sap found in rubber trees, Hevea brasiliensis,which is used to make numerous products we use today.[1][2] Latex is ubiquitous in health care, making up much of the equipment used, including catheters, balloons, andmost commonly, gloves.[3][4][5] There own been hundreds of allergens identified from natural rubber latex (NRL) with 15 official ones given numbers (Hev b1 to Hev b15).[6][7][8] The natural proteins in rubber are associated with both asymptomatic sensitization and type I IgE-mediated hypersensitivity.[2] During latex processing, chemical antioxidants are added, which can cause type IV hypersensitivity reactions as well.

    Latex allergy is among the most common causes of anaphylaxis in the operating room and has increased in prevalencewith the increased use of latex gloves to prevent transmittable infections starting in the s.[7][9][8] A significant increase in the production of latex gloves has resulted in a widespread occurrence of allergies to latex.[9] Latex allergy has also become a well-known problem among healthcare workers while wearing gloves or inhaling aerosolized particles.

    a ANB, Turrini RNT. Perioperative latex hypersensitivity reactions: An integrative review.

    What is a type iv latex allergy

    Rev Lat Am Enfermagem ;20(2) []

    1. Mota ANB, Turrini RNT. Perioperative latex hypersensitivity reactions: An integrative review. Rev Lat Am Enfermagem ;20(2) []

    2. Galindo MJ, Quirce S, Olmos LG. Latex allergy in primary care providers. J Investig Allergol Clin Immunol ;21(6)

    2. Galindo MJ, Quirce S, Olmos LG. Latex allergy in primary care providers. J Investig Allergol Clin Immunol ;21(6)

    3. Palosuo T, Antoniadou I, Gottrup F, Phillips P. Latex medical gloves: Time for reappraisal. Int Arch Allergy Immunol ; []

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    Palosuo T, Antoniadou I, Gottrup F, Phillips P. Latex medical gloves: Time for reappraisal. Int Arch Allergy Immunol ; []

    4. Leung DY, Sampson HA, Geha R, Szefler SJ. Pediatric Allergy: Principles and Practice. 2nd ed. Edinburgh: Elsevier Saunders,

    4. Leung DY, Sampson HA, Geha R, Szefler SJ. Pediatric Allergy: Principles and Practice. 2nd ed. Edinburgh: Elsevier Saunders,

    5. Cabanes N, Ilgea JM, de La Hoz B. Latex allergy: Position paper. J Investig Allergol Clin Immunol h;22(5)

    5. Cabanes N, Ilgea JM, de La Hoz B. Latex allergy: Position paper. J Investig Allergol Clin Immunol h;22(5)

    6.

    Potter PC, Crombie I, Kosheva O, et al. Latex allergy at Groote Schuur Hospital &#x; prevalence, clinical features and outcome. S Afr Med J ;

    6. Potter PC, Crombie I, Kosheva O, et al. Latex allergy at Groote Schuur Hospital &#x; prevalence, clinical features and outcome. S Afr Med J ;

    7. Buss ZS, Kupek E, Frode TS. Screening for latex sensitization by questionnaire: Diagnostic performance in health care workers. J Investig Allergol Clin Immunol ;18(1)

    7.

    Buss ZS, Kupek E, Frode TS. Screening for latex sensitization by questionnaire: Diagnostic performance in health care workers. J Investig Allergol Clin Immunol ;18(1)

    8. Steinman H, Ruden S. ImmunoCAP, native and recombinant allergen components. Allergy &#x; Which Allergen? Phadia AB,

    8. Steinman H, Ruden S.

    What is a type iv latex allergy

    ImmunoCAP, native and recombinant allergen components. Allergy &#x; Which Allergen? Phadia AB,

    9. Ismail NA, Hoosen AA, Mehtar S. Latex allergy in health care workers: Prevalence and knowledge at a tertiary teaching hospital in a developing country. International Journal of Infection Control ;6(1) []

    9.

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    Ismail NA, Hoosen AA, Mehtar S. Latex allergy in health care workers: Prevalence and knowledge at a tertiary teaching hospital in a developing country. International Journal of Infection Control ;6(1) []

    Potter PC. Latex allergy in Southern Africa.

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    Allergy and Clinical Immunology International ;14(1) []

    Potter PC. Latex allergy in Southern Africa. Allergy and Clinical Immunology International ;14(1) []

    Braithwaite N, Motala C, Toerten A. Latex allergy &#x; the Red Cross Children&#x;s Hospital experience. S Afr Med J ;91(9)

    Braithwaite N, Motala C, Toerten A. Latex allergy &#x; the Red Cross Children&#x;s Hospital experience. S Afr Med J ;91(9)

    Allmers H, Schmengler J, Malte S. Decreasing incidence of occupational contact urticaria caused by natural rubber latex allergy in German health care workers. J Allergy Clin Immunol ;(2) []

    Allmers H, Schmengler J, Malte S.

    Decreasing incidence of occupational contact urticaria caused by natural rubber latex allergy in German health care workers. J Allergy Clin Immunol ;(2) []

    Allmers H, Schmengler J, Skudlik C. Primary prevention of natural rubber latex allergy in the German health care system through education and intervention. J Allergy Clin Immunol ;(2) []

    Allmers H, Schmengler J, Skudlik C. Primary prevention of natural rubber latex allergy in the German health care system through education and intervention. J Allergy Clin Immunol ;(2) []

    Hamilton RG, Peterson EL, Ownby DR. Clinical and laboratory-based methods in the diagnosis of natural rubber latex allergy.

    J Allergy Clin Immunol ;SS []

    Hamilton RG, Peterson EL, Ownby DR. Clinical and laboratory-based methods in the diagnosis of natural rubber latex allergy. J Allergy Clin Immunol ;SS []

    Filon FL, Radman G. Latex allergy: A follow up study of healthcare workers. Occup Environ Med ; []

    Filon FL, Radman G. Latex allergy: A follow up study of healthcare workers. Occup Environ Med ; []

    Accepted 18 February

    Introduction

    Latex comes from a sap found in rubber trees, Hevea brasiliensis,which is used to make numerous products we use today.[1][2] Latex is ubiquitous in health care, making up much of the equipment used, including catheters, balloons, andmost commonly, gloves.[3][4][5] There own been hundreds of allergens identified from natural rubber latex (NRL) with 15 official ones given numbers (Hev b1 to Hev b15).[6][7][8] The natural proteins in rubber are associated with both asymptomatic sensitization and type I IgE-mediated hypersensitivity.[2] During latex processing, chemical antioxidants are added, which can cause type IV hypersensitivity reactions as well.

    Latex allergy is among the most common causes of anaphylaxis in the operating room and has increased in prevalencewith the increased use of latex gloves to prevent transmittable infections starting in the s.[7][9][8] A significant increase in the production of latex gloves has resulted in a widespread occurrence of allergies to latex.[9] Latex allergy has also become a well-known problem among healthcare workers while wearing gloves or inhaling aerosolized particles.


    Results

    A entire of HCWs (all nurses) returned the questionnaires and therefore participated in the baseline study, giving a participation rate of % (/).

    Doctors and cleaners did not return the questionnaires, perhaps because they did not regard themselves as being at risk for latex allergy. Demographic characteristics of the study participants are presented in Table 2.

    The mean age of the study participants was years (standard deviation (SD) years, range 20 — 60 years). There were more females (%) than males. Fourteen participants did not continue with the study due to: death (2), proving untraceable (4), and refusal to continue for personal reasons (8). Glove-related symptoms were present in 59 HCWs (%), of whom 7 (%) had positive SPTs to latex (95% confidence interval — %).

    Latex (K82) titres of the participants who tested positive were, in ascending order, kU/l, kU/l, kU/l, kU/l, kU/l, kU/l, and 45 kU/l. Thirty-eight participants with negative blood tests underwent SPTs, 5 of which were positive, with readings of 3 mm, 3 mm, 4 mm, 4 mm and 7 mm.

    Positive SPTs were reported in 5 out of 38 workers with negative blood tests (%), indicating that blood tests missed % of latex-allergic individuals (5/45). The prevalence of latex allergy among HCWs was % (12/), after adjusting for the 14 subjects lost to follow-up before SPT.

    The symptoms experienced were rhinitis in 12 (%), asthma in 6 (%), dermatitis in 3 (%), anaphylaxis requiring mechanical ventilation for 2 weeks in 1 (%), urticaria in 1 (%), abdominal pain in 1 (%) and angio-oedema in 1 (%).

    The number of latex-sensitised or allergic individual HCWs per workstation was also sure (Table 3). The proportion was highest among labour ward staff.

    Clinical symptoms in participants who met inclusion criteria for sensitisation testing

    The clinical symptoms of the participants are listed in Table 4.

    Of note is that 54 participants had more than one symptom. Among those who were positive to either the ImmunoCAP test or the SPT, symptoms were as follows: 5 had 1 symptom, 4 had 2 symptoms and the other 3 had 3 or more symptoms. Every the participants who tested positive had rhinitis, and half had asthma. There was no statistically significant difference between the sensitised (latex-positive) and non-sensitised (latex-negative) groups with regard to rhinitis, asthma, anaphylaxis requiring ventilation, abdominal pain, urticaria and angio-oedema (p>). A statistically significant association was observed with regard to dermatitis in terms of latex exposure in the two groups (p<).

     


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