Identifying gram-positive cocci in dermatoscopes and smartphone adapters using MALDI-TOF MS: a cross-sectional study<sup>,</sup>

Quadros, Maurício de; Bugs, Roberto Carlos Freitas; Soares, Renata de Oliveira; Rossato, Adriana Medianeira; Rocha, Lisiane da Luz; d'Azevedo, Pedro Alves

doi:10.1016/j.abd.2019.11.004

Maurício de Quadros ^** Corresponding author. E-mail:mdquadros@gmail.com (M. Quadros).

Gram-positive Cocci Laboratory, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS, Brazil

Department of Dermatology, Hospital Santa Casa de Misericórdia de Porto Alegre, Porto Alegre, RS, Brazil

http://orcid.org/0000-0003-1824-1729

Roberto Carlos Freitas Bugs

Gram-positive Cocci Laboratory, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS, Brazil

http://orcid.org/0000-0002-4097-6898

Renata de Oliveira Soares

Gram-positive Cocci Laboratory, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS, Brazil

http://orcid.org/0000-0002-8753-259X

Adriana Medianeira Rossato

Gram-positive Cocci Laboratory, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS, Brazil

http://orcid.org/0000-0001-5597-0790

Lisiane da Luz Rocha

Gram-positive Cocci Laboratory, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS, Brazil

http://orcid.org/0000-0002-4245-5789

Pedro Alves d'Azevedo

Gram-positive Cocci Laboratory, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS, Brazil

http://orcid.org/0000-0001-8539-7833

* Corresponding author. E-mail:mdquadros@gmail.com (M. Quadros).

Author's contributions

Maurício de Quadros: Statistic analysis; approval of the final version of the manuscript; conception and planning of the study; elaboration and writing of the manuscript; obtaining, analysis, and interpretation of the data; effective participation in research orientation; critical review of the literature; critical review of the manuscript.

Roberto Carlos Freitas Bugs: Approval of the final version of the manuscript; conception and planning of the study; obtaining, analysis, and interpretation of the data; critical review of the literature.

Renata de Oliveira Soares: Approval of the final version of the manuscript; conception and planning of the study; obtaining, analysis, and interpretation of the data; effective participation in research orientation.

Adriana Medianeira Rossato: Approval of the final version of the manuscript; conception and planning of the study; elaboration and writing of the manuscript; obtaining, analysis, and interpretation of the data; effective participation in research orientation; critical review of the literature; critical review of the manuscript.

Lisiane da Luz Rocha: Approval of the final version of the manuscript; conception and planning of the study; elaboration and writing of the manuscript; obtaining, analysis, and interpretation of the data; critical review of the manuscript.

Pedro Alves d'Azevedo: Statistic analysis; approval of the final version of the manuscript; conception and planning of the study; elaboration and writing of the manuscript; obtaining, analysis, and interpretation of the data; effective participation in research orientation; critical review of the literature; critical review of the manuscript.

Conflicts of interest

None declared.

Variable	Descriptive measures
Age, years - mean ± SD	36.4 ± 8.4

Sex, n (%)
Male	16 (13.5)
Female	102 (86.5)
Time as a dermatologist, median - years (interquartile range)	6.5 (2-15)

Where do you attend patients? - n (%)
In the private office	47 (39.8)
At hospital	25 (21.2)
In the private office and at hospital	46 (39)
Number of times the dermatoscope id used per day - median (interquartile range)	15 (10-20)
Amount of time the dermatoscope is used during consultation, in minutes - median (interquartile range)	5 (3-7)

Model of dermatoscope, n (%)
DL100	6 (5.1)
DL200	2 (1.7)
DL3	24 (20.3)
DL4	34 (28.8)
Hybrid	42 (35.6)
MiniHeine or Heine	8 (6.8)
Wellch Allyn	1 (0.8)
Veos Canfield	1 (0.8)

Does the device touch the patient's skin during the examination? - n (%)
Yes	92 (78)
No	26 (22)

Where do you keep the dermatoscope? - n (%)
Coat pocket	68 (57.6)
Desktop	76 (64.4)
Wardrobe	21 (17.8)
Case	15 (12.7)

Do you use the dermatoscope in the private office? - n (%)
Yes	102 (86.4)
No	16 (13.6)

Do you use the dermatoscope at the hospital? - n (%)
Yes	64 (54.2)
No	54 (45.8)

Do you use the dermatoscope with inpatients? - n (%)
Yes	39 (33)
No	79 (67)

Do you use the dermatoscope in the ICU? - n (%)
Yes	20 (17)
No	98 (83)

Have you attended an inpatient in isolation due to multidrug resistant bacteria in the last 30 days? - n (%)
Yes	15 (12.7)
No	103 (87.3)

Have you used the dermatoscope on an inpatient with multidrug resistant bacteria in the last 30 days? - n (%)
Yes	2 (1.7)
No	116 (98.3)

Do you use any cleanser for the dermatoscope? - n (%)
Yes	92 (78)
No	26 (22)

Do you use a smartphone adapter? - n (%)
Yes	27 (22.9)
No	91 (77.1)

Variable	n/total	Frequency (%)	95% CI
Bacterial growth in the dermatoscope (lens or on/off button)	70/118	59.3	49.9-68.3
Bacterial growth in the lens	55/118	46.6	37.4-56.0
Bacterial growth on the on/off button	44/118	37.3	28.6-46.7
Bacterial growth on smartphone adapter	10/27	37	19.4-57.6

Variable	Frequency (n)	Contamination by gram positive cocci (%)	p-Value
Sex			0.581^a a Chi-squared test.
Male	11	68.8
Female	59	57.8

Resident			0.013^a a Chi-squared test.
Yes	33	75
No	37	50

Where do you attend?			0.010^a a Chi-squared test.
Private office	20	42.6
Hospital	18	72
Private office and hospital	32	69.6

Where do you attend?			0.005^a a Chi-squared test.
Only private office	20	42.6
Only hospital or private office plus hospital	50	70.4

Model of dermatoscope			0.361^a a Chi-squared test.
DL100 and DL200	4	50
DL3, DL4, Veos Canfield	37	62.7
Hybrid	26	61.9
Wellch Allyn or Heine	3	33.3

Does it touch the skin?			0.676^a a Chi-squared test.
Yes	56	60.9
No	14	53.8

Keep the dermatoscope in the coat pocket			0.019^a a Chi-squared test.
Yes	47	69.1
No	23	46

Put the dermatoscope on the table			0.819^a a Chi-squared test.
Yes	44	57.9
No	26	61.9

Store the dermatoscope in a closet			0.999^a a Chi-squared test.
Yes	12	57.1
No	58	59.8

Store the dermatoscope in a case			0.735^a a Chi-squared test.
Yes	10	66.7
No	60	58.3

Do you use the dermatoscope in the private office?			0.272^a a Chi-squared test.
Yes	58	56.9
No	12	75.0

Do you use the dermatoscope at the hospital?			0.001^a a Chi-squared test.
Yes	47	73.4
No	23	42.6

Do you use the dermatoscope with inpatients?			<0.001^a a Chi-squared test.
Yes	33	84.6
No	37	46.8

Do you use the dermatoscope in the ICU?			<0.001^a a Chi-squared test.
Yes	20	100
No	50	51

Have you attended patients in isolation due to multidrug resistant bacteria in the last 30 days?			0.143^a a Chi-squared test.
Yes	12	80
No	58	56.3

Have you used the dermatoscope on a patient with multidrug resistant bacteria in the last 30 days?			0.513^b b Fisher's exact test.
Yes	2	100
No	68	58.6

Do you clean the dermatoscope?			0.348^a a Chi-squared test.
Yes	52	56.5
No	18	69.2

Do you use a smartphone adapter?			0.999^a a Chi-squared test.
Yes	16	59.3
No	54	59.3

Variable	Presence of gram-positive median cocci (interquartile range)	Absence of gram-positive-median cocci (interquartile range)	p-Value
Time as a dermatologist, years	4 (1-11.25)	11 (4.25-18)	<0.001
Number of times the dermatoscope is used per day	15 (10-20)	10 (10-16.5)	0.004
Number of patients seen per day	20 (15-25)	15.5 (12.25-20)	0.035
Dermoscopy time per consultation, minutes	5 (3-7.25)	5 (3-5)	0.881
How many times a day do you access your mobile phone?	10 (4.75-15)	10 (5-15)	0.862

	Gram-positive cocci
	Sensitivity		Resistance
Antibiotic	n	%	n	%
Penicillin	26	23.6	84	77.4
Erythromycin	31	28.4	78	71.6
Clindamycin	75	68.8	34	31.2
Tetracycline	95	86.4	15	13.6
SMT-TMP	66	60.6	43	39.4
Cefoxitin	103	93.6	7	6.4
Gentamicin	104	94.5	6	5.5
Rifampicin	105	95.4	5	4.6
Levofloxacin	103	93.6	7	6.4
Linezolid	110	100	0	0

	Frequency of resistance among gram-positive cocci (%)
Antibiotic	S. epidermidis	S. hominis	S. warneri	S. capitis	S. haemolyticus
Penicillin	79.4	50	88.9	75	100
Erythromycin	73.6	83.3	55.6	50	80
Clindamycin	36.6	25	11.1	0	40
Tetracycline	15.1	8.3	0	25	40
SMT-TMP	44.4	25	22.2	50	60
Cefoxitin	6.8	0	0	25	20
Gentamicin	5.5	0	0	0	40
Rifampicin	4.1	0	0	25	0
Levofloxacin	5.5	0	0	75	0
Linezolid	0	0	0	0	0

[1] * Corresponding author. E-mail:mdquadros@gmail.com (M. Quadros).

Brasil

Brasil

Abstract

Background:

Objectives:

Methods:

Results:

Study limitations:

Conclusion: