Effect of cannabis use on oral candidal carriage
M. R. Darling, T. M. Arendorf and N. A. Coldrey University ot ttie Western Cape, Cape Town, South Afrtca
Darling MR, Arendorf TM, Coldrey NA: Effect of cannabis use on oral candidal carriage, J Oral Pathol Med 1990; 19: 319-21, The effeets of cigarette smoking on oral candidal carriage and eandidosis have been well documented but few similar studies on cannabis smoking have appeared, therefore it was felt that sueh a study needed to be undertaken. In this investigation, the effect of eannabis smoking combined with methaqualone and tobacco on candidal prevalenee, density and candidosis was examitied in 55 users. Age and sex matched tobacco-smoking (;? = 58) and non-smoking controls {n = 50) were examined similarly. The imprint culture technique was used for harvesting Candida. Results showed an increased prevalence and density of C, albicans in cannabis users while there was no apparent differenee in the prevalence of candidiasis. However, two subjects presented with oral multifocal candidiasis.
The abuse of cannabis (marijuana) in the Western Cape area of South Afriea is a well-known phenomenon. The smoking of the "white pipe", a mixture of cannabis and small amounts of cigarette tobacco and crushed methaqualone tablets in a bottle neck, is a feature exclusive to South Africa (1), Few South Africans smoke "pure" cannabis. The effects of cigarette smoking on oral candidal carriage have been well documented (2-4), but few similar studies on eannabis smoking have appeared, therefore, it was felt that such a study needed to be undertaken. The objective of this study was to detennine the effeets of cannabis smoking on oral candidiasis as well as the oral prevalence and density of C. albicans. Material and methods
In 55 cannabis/methaqualone/tobacco users, the presence and density of colonisation on the dorsum of the tongue by C, albicas was determined. This site was chosen as it has been demonstrated that in man, the posterior dorsum of the tongue forms the primary oral reservoir for Candida (5), ARENDORF & WALKER'S (5) imprint culture technique was used for harvesting Candida. These authors demonstrated the superiority of this technique over others for determining the prevalence and density of Candida on the oral mucosa. Sterile squares of foam rubber (2,5 x 2,5 cm) were dipped in sterile Sabouraud's dextrose broth and placed on the posterior dorsum of the tongue for 60 s.
The foam pad was then pressed firmly on to a dry Sabouraud's dextrose agar plate, and incubated at 37 °C for 4-6 h. The foam pad was removed and reincubated at 37°C, The density of Candida on each plate was determined using a Gallenkamp colony counter. Counts were made after 24 and 48 h incubation. The selective media used for culture of the yeasts were Sabouraud's dextrose broth and Sabouraud's dextrose agar. These contained Novocillin (1,5 mgprocaine penicillin per ml; Novo Industries) and Novostrep (5 mg streptomycin sulfate per 3 ml; Novo Industries) to inhibit the growth of competing bacteria, C. albicans was identified using sugar fermentation and assimilation tests (6, 7) as well as germ tube formation (8), Other yeasts were not identified. Age and sex matched tobacco-smoking (77 = 58) and non-smoking controls (77 = 50) were also examined for the presence and density of C, albicans.
Key words: Candtda: candidal density: candidal prevalence; cannabis: oral candidiasis. M. R. Darling, Faculty of Dentistry, University of the Western Cape, Private Bag X12, Tygerberg 7505, South Africa. Accepted for publication May 20, 1990,
had an associated angular cheilitis and another herpes labialis, and one wore a removable partial denture. None of these patients had tnedian rhomboid glossitis (MRG), which has previously been associated with denture stomatitis and denture-wearing (9-11), One patient had an angular cheilitis only and another had MRG with an associated angular eheilitis; the former patient was dentate while the latter wore full upper and lower dentures. From the above it can be deduced that two patients had multifocal candidosis (10), A comparison by age of the three groups revealed no significant difference (ehisquare test, P = 0,0632), Candidal prevalence, shown in Tables 1 and 2, was significantly increased in the study group (chi-square, P = 0,022), Candidal density (Table 3) was determined for those subjects in whom Candida was present. It was also increased, and the difference between the study group and control groups approached significanee (/>> 0,2598),
Resuits
Five of the study group sampled for C. albicans wore full upper and lower dentures, one wore a full upper denture and three wore removable upper partial dentures. All the full upper and lower denture wearers and otie retnovable partial denture wearer were positive for C. albicans, while the ftill upper and the other two retnovable partial denture wearers were negative. Four of the satnple had a denture stotnatitis. Of these, three wore full upper and lower dentures of whom one
Discussion Oral candidjasis
Inhibition of the immune response in cannabis smokers has been reported (12-14) and has been associated with a recurrent genital herpes sitnplex (15), It would therefore not be surprising for oral candidosis to be found in chronic cannabis users. ARENDORF & WALKER (11) have suggested that tobacco stnoking and denture wearing may play a role in the development of MRG by favoring the lo-
320
D A R L I N G ET AL.
Table 1, Candidal prevalence: comparison between CN, CI and C2, showing presence and absence of Candida on subjects. (CN: n = 55; CI: 11 = 50; C2:n= 58), Absent
Present
%
21 38,2%
34 61.8%
%
32 64,0%
18 36.0%
33 46.9%
25 43,1%
CN CI C2
(n)
Key: CN = cannabis/methaqualone/tobacco smokers. CI = non-smoking controls. C2 = tobcco-smoking controls. Table 2. Candidal prevalence (continued): Comparison between CN and C I , CN and C2, CI and C2,
ing to some workers (2, 5), Controversy exists, however, as others have shown no significant difference in the prevalence of C. albicans in the mouths of tobacco smokers and non-smokers (3, 4, 22), The results of the current investigation suggest that cannabis smoking increases the intraoral prevalence of C, albicans, while cigarette smoking does not. The latter fmding contrasts with that of ARENDORF & WALKER (2), who found a prevalence of 70% in smokers, but is eonsistent with thefindingsof BASTIAAN & RHADE (3) and OLIVER & SHILLITOE (4) who found no difference. Another report by ARENDORF et al.
(23) revealed that significantly more smokers yielded yeast than non-smokers, but no difference was apparent with CN V CI CN V C2 CI V C2 respect to C, albicans. It is noteworthy Chi-square /> = 0.008 /> = 0,047 P = 0,452 that BASTIAAN & READE (3) did no colony counts and harvested C, albicans Key: as for Table I. from the left and right buecal mucosae and palate which are areas of low colocal proliferation of C. albicans on the nization (2, 4), dorsum of the tongue, afindingsupIt has been suggested that cigarette ported by other studies (16-18), In addi- smoking may cause a mild, clinically tion, they have found the posterior dor- undetectable alteration in the oral musum of the tongue to be the primary cosa which facilitates the colonization oral reservoir for C, albicans in carriers and growth of C. albicans (2), This may (2), An increased density of Candida was be true for cannabis smoke as well, seen in cannabis smokers. This habit Cannabis smoke and condensate may could be a eofactor which encourages provide nutrition for C. albicans. DONcandidal growth on the mucosa with ALD (24) has said that cannabis smoke resultant MRG and angular cheilitis as contains numerous hydrocarbons, simseen in this study. ilar to those in cigarette smoke. Certain We postulate that a eombination of Candida species are known to utilise hypoor denture hygiene, deficient nutri- drocarbons as a source of energy (4), tional factors (19-21) and cannabis use and may play a causal role in the develcontributed to the manifestations of opment of oral cancer by means of encandidiasis (including 2 multifocal dogenous nitrosamine production (25), manifestations) in these patients. There None of the patients in the eurrent was no significant difference between investigation were known diabetics. the study group an eontrols with regard This condition is reported to predispose to candidiasis, but none of the latter to candidal colonization and infection exhibited the ehronic multifocal form of of the mouth but local contributing facthe disease. tors eg, smoking and denture wearing, may be additionally identified (26), Prevalence of C. albicans
Density of C. albicans
The earrier rate of C. albicans is higher Interestingly, eannabis users who were in smokers than in non-smokers accord- candidal carriers had a mean density
of nearly twice as many yeast colonies (51,2) as non-smoking controls (28,6) and cigarette-smoking controls (33,6) and this difference approached significance. This was probably not related to oral hygiene practices as there were no apparent differences in this factor or periodontal disease status between cannabis smokers and controls, or between carriers and non-carriers. There was also no significant difference in the prevalence of denture wearers or denture stomatitis between cannabis users and controls, OLIVER & SHILLITOE (4) found that cigarette smokers who were carriers had a mean of twice as many yeast eells per ml of saliva as did non-smoking carriers. This is supported, in part, by the findings of the current investigation. In eonclusion, the results of this investigation indicate that cannabis smoking significantly increases the prevalence of oral carriage of C. albicans. While cannabis smoking did not appear to significantly affect the density of colonisation of Candida, eomparison with controls showed that the difference approached significance. This habit did not increase the prevalence of oral candidosis in the study group. The effect of methaqualone and tobacco is likely to be limited by the fact that only small quantities are used. Acknowledgments - The authors are grateful to G, JouBERT of the Medical Research Council for conducting the statistical procedures. References 1. DE MIRANDA S, ed. Drugs and drug abu.se in southern Africa. Pretoria: J, L. van Schaik, 1987: 8-49. 2. ARENDORF TM, WALKER DM. The prev-
alence and intra-oral distribution oi Candida albicans in man. Arch Oral Biol 1980; 25: 1-10. 3. BAsriAAN RJ, READE PC, The prevalence of Candida albicans in the mouths of tobaeeo smokers with and without oral mucous membrane keratoses. Oral Surg Oral Med Orat Pattwt 1982; 53: 148-51. 4. OLIVER DE, SHILLITOE EJ. Dffects
Table 3, Candidal density: number of colonies was compared in those patients who demonstrated candidal presence.
Mean no, of colonies Standard deviation 75 percentile 50% median 25 percentile Key: as for Table 1.
CN (« = 34)
CI («=I8)
C2 (n = 25)
5L2 125,5 22,3 9,5 2,8
28.6 55.2 25.8 2.0 1,0
33.6 55.4 50.5 9.0 2.0
of
smoking on the prevalence and intraoral distribution of Candida atbicans. J Orat Pathot 1984; 13: 265-70. 5. ARENDORF TM, WALKER DM, Oral can-
didal populations in health and disease, Br Dent J 1979; 147: 267-72, 6. DoLAN CT, A practical approach to identification of yeast-like organisms. Am J Ctin Pathot 1971; 55: 580-90, 7. HALEY L D . Identification of yeasts in clinical microbiology laboratories. Am J
Cannabis effect on oral Candida 321 Med Technol 1971; 4: 125-31. 8. TASCHDJIAN C L , BURCHALL JJ, KOZIN
PJ. Rapid identification of Candida albicans by filamentation on serum or serum substitutes. Am J Dis Child 1960; 99: 212-15. 9. BuDTZ-JORGENSEN E. Denture stomatitis (V). Candida agglutinins in human sera. Acta Odontol Scand 1972; 30: 313-25. 10.
HOLMSTRUP P, BESSERMAN M . Clinical,
therapeutic, and pathogenic aspects of chronic oral multifocal candidosis. Oral Surg Oral Med Oroal Pathol 1983; 56: 388-95. 11. ARENDORF TM, WALKER DM. Tobaeeo
smoking and denture wearing as local aetiological factors in median rhomboid glossitis. Int J Oral Surg 1984; 13: 411-5. 12. NAHAS G G , Suciu-FocA N, ARMAND JP,
MoRiSHiMA A. Inhibition of cellular mediated immunity in marijuana smokers. Science 1974; 183: 419-20. 13. WHITE SC. BRIN SC, JANICKI B W . Mito-
gen-induced blastogenic responses of lymphocytes from marijuana smokers.
candidosis: L Clinicopathological asScience 1975; 188: 71-2. pects. Dent Uptake 1988; 15: 227-31. 14. BARON JD, ed. Kids and drugs. New 22. COLEMAN G , BEIGHTON D , CHALK A, York: Putnam, 1983; 15-27. WAKE S. Cigarette smoking and the mi15. JUEL-JENSEN B E . Cannabis and recurrent crobial flora of the mouth. Aust Dent J Herpes simplex. Br Med J 1972; 4: 296 1976; 21: 111-8. (only). 23. ARENDORF TM, ALDRED MJ, MORRIS 16. CooKE BED. Median rhomboid glossitis. DB, MURPHY JP. Intra-oral yeasts in an Candidiasis and not a developmental indigent South African community. J anomaly. Br J Dermatol 1975; 93: Dent Assoc S Afr 1986; 41: 327-30. 399-405. 24. DONALD PJ. Marijuana smoking - Pos17. WRIGHT BA, FENWICK F . Candidiasis sible cause of head and neck carcinoma and atrophic tongue lesions. Oral Surg in young patients. Otolaryngol Head Oral Med Oral Pathol 1981; 51: 55-61. Neck Surg 1986; 94: 517-21. 18. TouYZ LZG, PETERS E . Candidal infec25. KROGH P, HALD B , HOLMSTRUP P. Postion of the tongue with non-specific insible mycological etiology of oral mucoflammation of the palate. Oral Surg Oral sal cancer: catalytic potential of infecting Med Oral Pathol 1987; 63: 304-8. Candida albicans and other yeasts in pro19. JENKINS W M M , MACFARLANE TW, FERduction of N-nitrosobenzylmethylamiGUSON MM, MASON D K . Nutritional ne.Carcinogenesis 1987; 8: 1543-8. deficiency in oral candidosis. Int J Oral Surg \911; 6. 204-10. 26. TAPPER-JONES LM, ALDRED MJ, WALKER DM, HAYES TM. Candidal infections 20. SAMARANAYAKE LP. Nutritional factors and populations of Candida albicans in and oral candidosis. J Oral Pathol 1986; mouths of diabetics. J Clin Pathot 1981; 15: 61-5. 34:706-11. 21. SAMARANAYAKE LP, LAMEY P-J. Oral
M. R. Darling, T. M. Arendorf and N. A. Coldrey University ot ttie Western Cape, Cape Town, South Afrtca
Darling MR, Arendorf TM, Coldrey NA: Effect of cannabis use on oral candidal carriage, J Oral Pathol Med 1990; 19: 319-21, The effeets of cigarette smoking on oral candidal carriage and eandidosis have been well documented but few similar studies on cannabis smoking have appeared, therefore it was felt that sueh a study needed to be undertaken. In this investigation, the effect of eannabis smoking combined with methaqualone and tobacco on candidal prevalenee, density and candidosis was examitied in 55 users. Age and sex matched tobacco-smoking (;? = 58) and non-smoking controls {n = 50) were examined similarly. The imprint culture technique was used for harvesting Candida. Results showed an increased prevalence and density of C, albicans in cannabis users while there was no apparent differenee in the prevalence of candidiasis. However, two subjects presented with oral multifocal candidiasis.
The abuse of cannabis (marijuana) in the Western Cape area of South Afriea is a well-known phenomenon. The smoking of the "white pipe", a mixture of cannabis and small amounts of cigarette tobacco and crushed methaqualone tablets in a bottle neck, is a feature exclusive to South Africa (1), Few South Africans smoke "pure" cannabis. The effects of cigarette smoking on oral candidal carriage have been well documented (2-4), but few similar studies on eannabis smoking have appeared, therefore, it was felt that such a study needed to be undertaken. The objective of this study was to detennine the effeets of cannabis smoking on oral candidiasis as well as the oral prevalence and density of C. albicans. Material and methods
In 55 cannabis/methaqualone/tobacco users, the presence and density of colonisation on the dorsum of the tongue by C, albicas was determined. This site was chosen as it has been demonstrated that in man, the posterior dorsum of the tongue forms the primary oral reservoir for Candida (5), ARENDORF & WALKER'S (5) imprint culture technique was used for harvesting Candida. These authors demonstrated the superiority of this technique over others for determining the prevalence and density of Candida on the oral mucosa. Sterile squares of foam rubber (2,5 x 2,5 cm) were dipped in sterile Sabouraud's dextrose broth and placed on the posterior dorsum of the tongue for 60 s.
The foam pad was then pressed firmly on to a dry Sabouraud's dextrose agar plate, and incubated at 37 °C for 4-6 h. The foam pad was removed and reincubated at 37°C, The density of Candida on each plate was determined using a Gallenkamp colony counter. Counts were made after 24 and 48 h incubation. The selective media used for culture of the yeasts were Sabouraud's dextrose broth and Sabouraud's dextrose agar. These contained Novocillin (1,5 mgprocaine penicillin per ml; Novo Industries) and Novostrep (5 mg streptomycin sulfate per 3 ml; Novo Industries) to inhibit the growth of competing bacteria, C. albicans was identified using sugar fermentation and assimilation tests (6, 7) as well as germ tube formation (8), Other yeasts were not identified. Age and sex matched tobacco-smoking (77 = 58) and non-smoking controls (77 = 50) were also examined for the presence and density of C, albicans.
Key words: Candtda: candidal density: candidal prevalence; cannabis: oral candidiasis. M. R. Darling, Faculty of Dentistry, University of the Western Cape, Private Bag X12, Tygerberg 7505, South Africa. Accepted for publication May 20, 1990,
had an associated angular cheilitis and another herpes labialis, and one wore a removable partial denture. None of these patients had tnedian rhomboid glossitis (MRG), which has previously been associated with denture stomatitis and denture-wearing (9-11), One patient had an angular cheilitis only and another had MRG with an associated angular eheilitis; the former patient was dentate while the latter wore full upper and lower dentures. From the above it can be deduced that two patients had multifocal candidosis (10), A comparison by age of the three groups revealed no significant difference (ehisquare test, P = 0,0632), Candidal prevalence, shown in Tables 1 and 2, was significantly increased in the study group (chi-square, P = 0,022), Candidal density (Table 3) was determined for those subjects in whom Candida was present. It was also increased, and the difference between the study group and control groups approached significanee (/>> 0,2598),
Resuits
Five of the study group sampled for C. albicans wore full upper and lower dentures, one wore a full upper denture and three wore removable upper partial dentures. All the full upper and lower denture wearers and otie retnovable partial denture wearer were positive for C. albicans, while the ftill upper and the other two retnovable partial denture wearers were negative. Four of the satnple had a denture stotnatitis. Of these, three wore full upper and lower dentures of whom one
Discussion Oral candidjasis
Inhibition of the immune response in cannabis smokers has been reported (12-14) and has been associated with a recurrent genital herpes sitnplex (15), It would therefore not be surprising for oral candidosis to be found in chronic cannabis users. ARENDORF & WALKER (11) have suggested that tobacco stnoking and denture wearing may play a role in the development of MRG by favoring the lo-
320
D A R L I N G ET AL.
Table 1, Candidal prevalence: comparison between CN, CI and C2, showing presence and absence of Candida on subjects. (CN: n = 55; CI: 11 = 50; C2:n= 58), Absent
Present
%
21 38,2%
34 61.8%
%
32 64,0%
18 36.0%
33 46.9%
25 43,1%
CN CI C2
(n)
Key: CN = cannabis/methaqualone/tobacco smokers. CI = non-smoking controls. C2 = tobcco-smoking controls. Table 2. Candidal prevalence (continued): Comparison between CN and C I , CN and C2, CI and C2,
ing to some workers (2, 5), Controversy exists, however, as others have shown no significant difference in the prevalence of C. albicans in the mouths of tobacco smokers and non-smokers (3, 4, 22), The results of the current investigation suggest that cannabis smoking increases the intraoral prevalence of C, albicans, while cigarette smoking does not. The latter fmding contrasts with that of ARENDORF & WALKER (2), who found a prevalence of 70% in smokers, but is eonsistent with thefindingsof BASTIAAN & RHADE (3) and OLIVER & SHILLITOE (4) who found no difference. Another report by ARENDORF et al.
(23) revealed that significantly more smokers yielded yeast than non-smokers, but no difference was apparent with CN V CI CN V C2 CI V C2 respect to C, albicans. It is noteworthy Chi-square /> = 0.008 /> = 0,047 P = 0,452 that BASTIAAN & READE (3) did no colony counts and harvested C, albicans Key: as for Table I. from the left and right buecal mucosae and palate which are areas of low colocal proliferation of C. albicans on the nization (2, 4), dorsum of the tongue, afindingsupIt has been suggested that cigarette ported by other studies (16-18), In addi- smoking may cause a mild, clinically tion, they have found the posterior dor- undetectable alteration in the oral musum of the tongue to be the primary cosa which facilitates the colonization oral reservoir for C, albicans in carriers and growth of C. albicans (2), This may (2), An increased density of Candida was be true for cannabis smoke as well, seen in cannabis smokers. This habit Cannabis smoke and condensate may could be a eofactor which encourages provide nutrition for C. albicans. DONcandidal growth on the mucosa with ALD (24) has said that cannabis smoke resultant MRG and angular cheilitis as contains numerous hydrocarbons, simseen in this study. ilar to those in cigarette smoke. Certain We postulate that a eombination of Candida species are known to utilise hypoor denture hygiene, deficient nutri- drocarbons as a source of energy (4), tional factors (19-21) and cannabis use and may play a causal role in the develcontributed to the manifestations of opment of oral cancer by means of encandidiasis (including 2 multifocal dogenous nitrosamine production (25), manifestations) in these patients. There None of the patients in the eurrent was no significant difference between investigation were known diabetics. the study group an eontrols with regard This condition is reported to predispose to candidiasis, but none of the latter to candidal colonization and infection exhibited the ehronic multifocal form of of the mouth but local contributing facthe disease. tors eg, smoking and denture wearing, may be additionally identified (26), Prevalence of C. albicans
Density of C. albicans
The earrier rate of C. albicans is higher Interestingly, eannabis users who were in smokers than in non-smokers accord- candidal carriers had a mean density
of nearly twice as many yeast colonies (51,2) as non-smoking controls (28,6) and cigarette-smoking controls (33,6) and this difference approached significance. This was probably not related to oral hygiene practices as there were no apparent differences in this factor or periodontal disease status between cannabis smokers and controls, or between carriers and non-carriers. There was also no significant difference in the prevalence of denture wearers or denture stomatitis between cannabis users and controls, OLIVER & SHILLITOE (4) found that cigarette smokers who were carriers had a mean of twice as many yeast eells per ml of saliva as did non-smoking carriers. This is supported, in part, by the findings of the current investigation. In eonclusion, the results of this investigation indicate that cannabis smoking significantly increases the prevalence of oral carriage of C. albicans. While cannabis smoking did not appear to significantly affect the density of colonisation of Candida, eomparison with controls showed that the difference approached significance. This habit did not increase the prevalence of oral candidosis in the study group. The effect of methaqualone and tobacco is likely to be limited by the fact that only small quantities are used. Acknowledgments - The authors are grateful to G, JouBERT of the Medical Research Council for conducting the statistical procedures. References 1. DE MIRANDA S, ed. Drugs and drug abu.se in southern Africa. Pretoria: J, L. van Schaik, 1987: 8-49. 2. ARENDORF TM, WALKER DM. The prev-
alence and intra-oral distribution oi Candida albicans in man. Arch Oral Biol 1980; 25: 1-10. 3. BAsriAAN RJ, READE PC, The prevalence of Candida albicans in the mouths of tobaeeo smokers with and without oral mucous membrane keratoses. Oral Surg Oral Med Orat Pattwt 1982; 53: 148-51. 4. OLIVER DE, SHILLITOE EJ. Dffects
Table 3, Candidal density: number of colonies was compared in those patients who demonstrated candidal presence.
Mean no, of colonies Standard deviation 75 percentile 50% median 25 percentile Key: as for Table 1.
CN (« = 34)
CI («=I8)
C2 (n = 25)
5L2 125,5 22,3 9,5 2,8
28.6 55.2 25.8 2.0 1,0
33.6 55.4 50.5 9.0 2.0
of
smoking on the prevalence and intraoral distribution of Candida atbicans. J Orat Pathot 1984; 13: 265-70. 5. ARENDORF TM, WALKER DM, Oral can-
didal populations in health and disease, Br Dent J 1979; 147: 267-72, 6. DoLAN CT, A practical approach to identification of yeast-like organisms. Am J Ctin Pathot 1971; 55: 580-90, 7. HALEY L D . Identification of yeasts in clinical microbiology laboratories. Am J
Cannabis effect on oral Candida 321 Med Technol 1971; 4: 125-31. 8. TASCHDJIAN C L , BURCHALL JJ, KOZIN
PJ. Rapid identification of Candida albicans by filamentation on serum or serum substitutes. Am J Dis Child 1960; 99: 212-15. 9. BuDTZ-JORGENSEN E. Denture stomatitis (V). Candida agglutinins in human sera. Acta Odontol Scand 1972; 30: 313-25. 10.
HOLMSTRUP P, BESSERMAN M . Clinical,
therapeutic, and pathogenic aspects of chronic oral multifocal candidosis. Oral Surg Oral Med Oroal Pathol 1983; 56: 388-95. 11. ARENDORF TM, WALKER DM. Tobaeeo
smoking and denture wearing as local aetiological factors in median rhomboid glossitis. Int J Oral Surg 1984; 13: 411-5. 12. NAHAS G G , Suciu-FocA N, ARMAND JP,
MoRiSHiMA A. Inhibition of cellular mediated immunity in marijuana smokers. Science 1974; 183: 419-20. 13. WHITE SC. BRIN SC, JANICKI B W . Mito-
gen-induced blastogenic responses of lymphocytes from marijuana smokers.
candidosis: L Clinicopathological asScience 1975; 188: 71-2. pects. Dent Uptake 1988; 15: 227-31. 14. BARON JD, ed. Kids and drugs. New 22. COLEMAN G , BEIGHTON D , CHALK A, York: Putnam, 1983; 15-27. WAKE S. Cigarette smoking and the mi15. JUEL-JENSEN B E . Cannabis and recurrent crobial flora of the mouth. Aust Dent J Herpes simplex. Br Med J 1972; 4: 296 1976; 21: 111-8. (only). 23. ARENDORF TM, ALDRED MJ, MORRIS 16. CooKE BED. Median rhomboid glossitis. DB, MURPHY JP. Intra-oral yeasts in an Candidiasis and not a developmental indigent South African community. J anomaly. Br J Dermatol 1975; 93: Dent Assoc S Afr 1986; 41: 327-30. 399-405. 24. DONALD PJ. Marijuana smoking - Pos17. WRIGHT BA, FENWICK F . Candidiasis sible cause of head and neck carcinoma and atrophic tongue lesions. Oral Surg in young patients. Otolaryngol Head Oral Med Oral Pathol 1981; 51: 55-61. Neck Surg 1986; 94: 517-21. 18. TouYZ LZG, PETERS E . Candidal infec25. KROGH P, HALD B , HOLMSTRUP P. Postion of the tongue with non-specific insible mycological etiology of oral mucoflammation of the palate. Oral Surg Oral sal cancer: catalytic potential of infecting Med Oral Pathol 1987; 63: 304-8. Candida albicans and other yeasts in pro19. JENKINS W M M , MACFARLANE TW, FERduction of N-nitrosobenzylmethylamiGUSON MM, MASON D K . Nutritional ne.Carcinogenesis 1987; 8: 1543-8. deficiency in oral candidosis. Int J Oral Surg \911; 6. 204-10. 26. TAPPER-JONES LM, ALDRED MJ, WALKER DM, HAYES TM. Candidal infections 20. SAMARANAYAKE LP. Nutritional factors and populations of Candida albicans in and oral candidosis. J Oral Pathol 1986; mouths of diabetics. J Clin Pathot 1981; 15: 61-5. 34:706-11. 21. SAMARANAYAKE LP, LAMEY P-J. Oral
