Background

A subgroup of autism-spectrum parents reports their child's persistent
problem with Candida. Within this subgroup, a goodly proportion report
traits improvement in response to anti-fungal therapy. These two subgroups
overlap with autism-spectrum subgroups defined by gf and/or cf diets.

Although Candida albicans colonizations are often described in immune
impaired patients (eg, 1-2), colonizations and more deeply embedded
infections can occur in patients described as immunocompetent (eg, 3-4). 

When comparing Candida albicans carrier-status within groups of
immunocompetent and immunocompromised patients, there is an association of
differing strains with the two groups (5).

Gastroinestinal Candida albicans has been documented in 100% of women with 
chronic vulvovaginitis, and in 26 percent, strain differences were noted
(6).

Esophageal candidiasis has been described as the most common occurrence
within the gastrointestinal tract (7); tissue damage accompanies
colonization (eg, 8); and -- as noted by many parents of autism-spectrum
children -- antibiotic therapy can incline towards colonization (9-11); and
there is an association between allergic phenomenon and Candida (12-13).;
and hypersensitivity to Candida albicans and other yeasts has been
described (14)

Candida albicans can exacerbate effects of certain strains of
Staphylococcus aureus (15) and has been associated with intestinal
perforation and peritonitis (16).

As cited, persistent Candida is associated with immune competent and immune
impaired individuals, with the latter group likelier to have sequelae
worthy of concern. Autism is associated with a variety of immune
atypicalities whose documentation indicates that a subgroup of autism-
spectrum children is at least to some extent immune impaired (eg, 17-19),
thereby increasing the likelihood of significant Candida. 

Furthermore, a series of studies by Luigina Romani, MD, and her colleagues
have shown that a Th2 pattern of immunity inclines towards persistent
Candida (20-22); and tendencies in a Th2 direction are associated with
autism (23). 

Parental anecdotes about persistent Candida albicans indicate (a) that many
children have gastrointestinal Candida colonizations that are not fully
immunosuppressed, and (b) that a subgroup of children so colonized
experiences improved traits as the colonization is treated and (when
possible) subsequent colonizations prevented by restoration of more
proibiotic flora.

This large body of anecdotal information is consistent with medical
research (a) about conditions predisposing to persistent Candida and (b)
about the existence of these conditions in a goodly subgroup of autism-
spectrum children (20-21).

1. Biochem Mol Biol Int 1998 Jan;44(1):19-27 
RAPD analysis of Candida albicans strains recovered from different
immunocompromised patients (ICP) reveals an apparently non-random
infectivity of the strains.
Gyanchandani A, Khan ZK, Farooqui N, Goswami M, Ranade SA

The opportunistic imperfect fungus Candida albicans causing
life-threatening infections in immunocompromised patients (ICP), especially
in HIV-positive cases, is recognized to be one of the most important
nosocomial pathogens in the recent decades. The extent of strain-to-strain
variation within a species and its relationship to the ability of the
organism to colonize or invade a specific group of patients or even a body
site is, however, not well known. We have analysed 19 strains of C.
albicans recovered from ICP at different locales and times, employing the
RAPD technique. No two strains generated identical RAPD profiles with any
of the 21 primers tested. Further, the UPGMA clustering of the strains
seemingly reflected a certain relationship or nonrandomness in the
infection of the patients with the strain of C. albicans vis-a-vis the
immunocompromised status due to underlying disease such as diabetes,
cancer, asthma and meningitis. These results may have a profound impact on
the management of candidiasis, especially in the ICP.

2. J Med Vet Mycol 1995 Jan-Feb;33(1):83-5 
In vitro susceptibility to itraconazole and fluconazole of switch
phenotypes of Candida albicans serotypes A and B, isolated from
immunocompromised hosts.
Velegraki A

3. Clin Infect Dis 1994 Dec;19(6):1179-80 
Fluconazole-resistant Candida albicans in an immunocompetent child.
Hennequin C, Labenne M, Benkerrou M, Hambourg M
Publication Types:  Letter

4. Eur J Clin Microbiol Infect Dis 1990 May;9(5):352-5 
Detection of an antibody response in immunocompetent patients with systemic
candidiasis or Candida albicans colonisation.
Porsius JC, van Vliet HJ, van Zeijl JH, Goessens WH, Michel MF

Tests to detect circulating antibodies to Candida albicans antigens were
performed in sera from 27 immunocompetent patients, 15 of whom had
deep-seated candidiasis and 12 of whom were colonised by Candida albicans.
For the diagnosis of deep-seated candidiasis in patients with either
deep-seated candidiasis or Candida albicans colonisation,
counterimmunoelectrophoresis had a sensitivity of 87% and a specificity of
75%. Using immunoblotting it could be shown that antibodies to 35K, 47K,
68K and 88K antigens of Candida albicans occurred more frequently in
patients with deep-seated candidiasis than in colonised patients. The
presence of dense bands in immunoblots representing antibodies against the
47K and/or 68K antigen served to discriminate significantly between
deep-seated and superficial candidiasis (p less than 0.05).

5. J Clin Microbiol 1989 Jun;27(6):1335-41 
Oral Candida albicans isolates from nonhospitalized normal carriers,
immunocompetent hospitalized patients, and immunocompromised patients with
or without acquired immunodeficiency syndrome.
Brawner DL, Cutler JE

A total of 128 human oral isolates of Candida albicans were collected from
asymptomatic healthy carriers (64 isolates); asymptomatic,
nonimmunosuppressed, hospitalized patients (25 isolates); immunosuppressed
transplant patients (19 isolates); and human immunodeficiency
virus-infected patients with symptoms of acquired immunodeficiency syndrome
and oral candidiasis (20 isolates). Isolates were serotyped as A or B and
tested for reactivity with an agglutinating immunoglobulin M monoclonal
antibody (H9). Immunocompetent individuals colonized by oral C. albicans
were almost equally likely to carry serotype A as serotype B cells, while
immunocompromised individuals were at least twice as likely to be infected
by serotype B than serotype A strains. The reactivity of isolates with H9
antibody followed a similar but more distinctive pattern. Approximately
half of the strains from immunocompetent individuals reacted strongly with
H9, and the remainder reacted weakly. However, up to 75% of the isolates
from immunocompromised patients reacted weakly with H9, while the remainder
reacted strongly. A correlation between H9 reactivity and the serotypes of
these isolates existed (P = 0.16). The correlation between H9 reactivity
and immune status was even stronger (P = 0.025). The monoclonal antibody
activities described above were determined by agglutination tests during
defined phases of C. albicans growth. Expression of antigen at various
times during growth of several isolates was confirmed at the cellular level
by analysis using fluorescence-activated cell sorting. Despite the
correlation between serotype A and H9 reactivity, H9 antigen was not
identical to the serotype A antigen because four serotype A strains reacted
only weakly with H9 antibody, and one strain reacted strongly with H9 but
was serotype B. These data indicate that oral strains of C. albicans from
immunocompetent individuals differ as a group from C. albicans isolated
from those who are immunosuppressed.

6. Mycoses 1990 Jan;33(1):24-8 
Interest of biotyping Candida albicans in chronic vulvovaginitis.
Poirier S, Auger P, Joly J, Steben M

Chronic vulvovaginitis due to Candida albicans is a major clinical problem
for the physician. Although new antifungal drugs are now available, the
therapeutic approach of this disease remains disappointing. The aims of
this study were two-fold. First, we wanted to evaluate the reliability of
a single sampling performed by most clinicians in verifying if the yeast
infects the entire genital mucosa or a preferential site and, second, to
biotype the strains recovered in order to see if more than one strain are
responsible for the infection. We found, in 18 patients suffering from
vaginal candidosis, that the entire genital mucosa was infected by the
yeast and the strain recovered from the different genital sites in a single
patient was the same in 100% of the cases. Only 1.4% of the samples were
negative. In addition, we biotyped the strains obtained from the
gastrointestinal tract of these patients to evaluate this site as a
potential source of infection. We obtained gastrointestinal tract samples
for 15 of the 18 patients and we could identify C. albicans in 100% of the
cases. Furthermore, 73.3% of the patients harboured the same strains of C.
albicans in the gastrointestinal tract as in the vagina.

7. J Gastroenterol 1994 Feb;29(1):1-5 
Significance of modes of adherence in esophageal Candida albicans.
Hoshika K, Mine H

Although esophageal candidiasis is the most common form of Candida
infection in the gastro-intestinal tract, little attention has been
directed toward determining the mechanism of its infection. We have already
clarified the existence of four modes of adherence of Candida albicans to
the esophagus; attachment, subepithelial cell insertion, cavitation, and
invasion. This study was undertaken to clarify the significance of each of
these modes. Scanning electron microscopic observations were made of
esophageal specimens from 8-week-old rabbits infected with Candida albicans
IFO 1060. In this study, attachment and subepithelial cell insertion were
found to be the most frequent modes of adherence. Cavitation occurred
following subepithelial cell insertion, while invasion occurred following
attachment and subepithelial cell insertion. These results suggest that
attachment and subepithelial cell insertion play the most important role in
the initial stage of adherence. The ratios of these modes for living yeast
cells were similar to those for dead yeast cells and beads. This suggests
that Candida albicans can gain a foothold on the esophageal epithelium
solely by physical contact, after which colonization occurs.

8. Infect Immun 1996 Nov;64(11):4514-9 
Evidence for degradation of gastrointestinal mucin by Candida albicans
secretory aspartyl proteinase.
Colina AR, Aumont F, Deslauriers N, Belhumeur P, de Repentigny L

A zone of extracellular digestion of the mucin layer around Candida
albicans blastoconidia was observed by transmission electron microscopy in
the jejunum of mice inoculated intragastrically (G. T. Cole, K. R. Seshan,
L. M. Pope, and R. J. Yancey, J. Med. Vet. Mycol. 26:173-185, 1988). This
observation prompted the hypothesis that a putative mucinolytic enzyme(s)
may contribute to the virulence of C. albicans by facilitating penetration
of the mucus barrier and subsequent adherence to and invasion of epithelial
cells. Mucinolytic activity was observed as zones of clearing around
colonies of C. albicans LAM-1 grown on agarose containing yeast nitrogen
base, glucose, and hog gastric mucin. In addition, concentrated culture
filtrate obtained after growth for 24 h in yeast nitrogen base,
supplemented with glucose and mucin as the sole nitrogen source, contained
proteolytic activity against biotin-labelled mucin which was inhibited by
pepstatin A. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of
the culture filtrate revealed two components of 42 and 45 kDa, with pIs of
4.1 and 5.3, respectively. A zymogram showed that mucin was degraded only
by the 42-kDa component, which was also recognized by immunoblotting with
an anti-secretory aspartyl proteinase (anti-Sap) 2p monoclonal antibody.
The N-terminal sequence of the first 20 amino acids matched that reported
for Sap2p. These results demonstrate that Sap2p is responsible for
proteolysis of mucin by C. albicans in vitro and may be involved as a
virulence factor in the breakdown of mucus and penetration of the mucin
barrier by C. albicans.

9. Mycoses 1989 Dec;32(12):664-74 
Candida albicans gastrointestinal colonization and invasion in the mouse:
effect of antibacterial dosing, antifungal therapy and immunosuppression.
Kinsman OS, Pitblado K

Infant mice infected with Candida albicans by the oral-intragastric route
became colonized in the gut and were persistently colonized into adulthood.
Faecal levels of Candida were correlated with total gastrointestinal
Candida and provided a useful means of detecting yeast overgrowth or
elimination. Antibacterial agents promoting Candida overgrowth when given
by the oral or parenteral route included ceftriaxone, augmentin and
cefoperazone. Ceftizoxime had less effect. Ceftazidime and latamoxef
produced raised levels only by the oral route. Gentamicin, vancomycin and
metronidazole did not affect the Candida levels. Dosing with some
antibacterials promoted an increase in gastrointestinal Candida and
invasion to a greater extent than immunosuppression. Antifungal therapy to
reduce gastrointestinal colonization was investigated using amphotericin B,
nystatin, ketoconazole, intraconazole and fluconazole. Fluconazole was most
effective at reducing faecal Candida.

10. J Med Microbiol 1987 Dec;24(4):333-41 
Mechanisms of association of Candida albicans with intestinal mucosa.
Kennedy MJ, Volz PA, Edwards CA, Yancey RJ

The association of Candida albicans with gastrointestinal (GI) mucosal
surfaces was studied in vitro and in vivo. The caecal mucosal surfaces from
antibiotic-treated and untreated control mice challenged orally with C.
albicans revealed that large numbers of C. albicans were associated with
the intestinal epithelium of antibiotic-treated mice but not with that of
the control mice that possessed an indigenous wall-associated bacterial
flora. Moreover, Candida cells only penetrated deep into the mucosa of
animals in which the ecology of the intestinal microflora had been
disrupted. In mice given antibiotics, C. albicans was associated with the
mucosa of all areas of the GI tract; the caecal mucosa had the most
associated Candida, whereas the stomach and small intestine had very few
associated yeasts. Further examination of caecal mucosa from
antibiotic-treated mice showed that C. albicans associated with the mucosa
by at least five distinct mechanisms. These included: adhesion to
epithelium, adhesion to mucus, co-adhesion to adherent fungi, co-adhesion
to adherent bacteria, and entrapment in the mucous gel overlying the
epithelium. The cell-surface hydrophobicity of C. albicans also was
examined and found not to play a role in Candida adhesion to intestinal
mucosa. The predominant association mechanisms appeared to be entrapment in
the mucous gel, and adhesion to mucus and the epithelium. The ecological
and pathological significance of co-adhesion by C. albicans to attached
organisms is unclear but it may be important in the initiation of mucosal
lesions.

11. Infect Immun 1985 Sep;49(3):654-63 
Ecology of Candida albicans gut colonization: inhibition of Candida
adhesion, colonization, and dissemination from the gastrointestinal tract
by bacterial antagonism.
Kennedy MJ, Volz PA

Antibiotic-treated and untreated Syrian hamsters were inoculated
intragastrically with Candida albicans to determine whether C. albicans
could opportunistically colonize the gastrointestinal tract and disseminate
to visceral organs. Antibiotic treatment decreased the total population
levels of the indigenous bacterial flora and predisposed hamsters to
gastrointestinal overgrowth and subsequent systemic dissemination by C.
albicans in 86% of the animals. Both control hamsters not given antibiotics
and antibiotic-treated animals reconventionalized with an indigenous
microflora showed significantly lower gut populations of C. albicans, and
C. albicans organisms were cultured from the visceral organs of 0 and 10%
of the animals, respectively. Conversely, non-antibiotic-treated hamsters
inoculated repeatedly with C. albicans had high numbers of C. albicans in
the gut, and viable C. albicans was recovered from the visceral organs of
53% of the animals. Examination of the mucosal surfaces from test and
control animals indicated further that animals which contained a complex
indigenous microflora had significantly lower numbers of C. albicans
associated with their gut walls than did antibiotic-treated animals. The
ability of C. albicans to associate with intestinal mucosal surfaces also
was tested by an in vitro adhesion assay. The results indicate that the
indigenous microflora reduced the mucosal association of C. albicans by
forming a dense layer of bacteria in the mucus gel, out-competing yeast
cells for adhesion sites, and producing inhibitor substances (possibly
volatile fatty acids, secondary bile acids, or both) that reduced C.
albicans adhesion. It is suggested, therefore, that the indigenous
intestinal microflora suppresses C. albicans colonization and dissemination
from the gut by inhibiting Candida-mucosal association and reducing C.
albicans population levels in the gut.

12. Allergy 1988 Apr;43(3):201-5 
Relationship of immediate and delayed hypersensitivity to nasopharyngeal
and intestinal growth of Candida albicans in allergic subjects.
Koivikko A, Kalimo K, Nieminen E, Viander M

The growth of C. albicans yeast in the nasopharynx and in the anus as well
as allergy symptoms were followed up for 8 months in 67 patients with
bronchial asthma, allergic rhinitis and/or atopic eczema. 38 of the
patients were skin prick test positive and 29 negative to C. albicans
allergen extract. 32 of the patients had positive and 19 negative delayed
skin reactions. The nasal, bronchial and skin symptoms of the
yeast-sensitive allergic patients were not associated with the
nasopharyngeal nor anal occurrence of C. albicans or other yeasts. The use
of nasal or inhaled steroids had no effect on the occurrence of Candida in
the nasopharynx. It was observed that immediate skin sensitivity had a
positive correlation and the delayed sensitivity a negative correlation
with the occurrence of C. albicans growth in nasopharynx and anus. These
findings are in agreement with the concept that impaired cell-mediated
immunity to C. albicans may lead to increased IgE response. This may
explain the increased liability towards C. albicans nasopharyngeal and
gastrointestinal "saprophytic" growth.

13. Allergol Immunopathol (Madr) 1975 Sep-Oct;3(5):289-98 
[Hypersensitivity to "Candida albicans" and other fungi in patients with
chronic urticaria]. [Article in Spanish]
Serrano H

Considering the high incidence of chronic urticaria among female patients
and the frequent difficulty in identifying the etiologic factor of factors
the author decided to investigate the possible role of Candida albicans and
other yeasts usually found as contaminants in certain foods and beverages
or purposely cultivated for industrial products, as the sensitizing agents
leading to the clinical picture of chronic urticaria. One hundred female
patients with urticaria which had persisted for more than 6 weeks were
selected and investigated, disregarding those with dermographism or
cholinergic and cold urticaria. Aside from a careful history and laboratory
tests to complement the physical examination that could rule out chronic
bacterial infectious foci, intestinal parasitic infestation and thyroid
disorders, intradermal skin tests with standard doses of Candida albicans
and Saccharomyces cerevisiae and other common environmental and food
allergens were done. The patients' age ranged from 4 to 70 years. The skin
tests sites were examined for Type I reactions at 15 and 20 minutes; for
Type III reactions at 8 and 12 hours; and for Type IV reactions at 48 and
72 hours. When tested with Candida albicans antigen, 35% had Type I/III
reactions and 60% presented Type IV reaction. When Saccharomyces cerevisiae
antigen was used for testing, 29% had Type I/III reactions and none
presented Type IV. Forty-nine of the sixty patients who presented Type IV
reaction to Candida albicans had in the past significant vaginal discharge
(or vaginal symptoms: burning, itching) that obliged the patients to
consult a gynecologist, but only ten had stained smears and cultures from
the vaginal secretions and four were told to have a monilia vaginal
infection confirmed by the microbiological tests, although forty of them
received Nistatin therapy at the time of the gynecological complaints. At
the time the patients were seen by the allergist, complaining about
urticaria, only four had symptoms and signs of monilia infection and were
confirmed by culture: one presented oral moniliasis following
broad-spectrum antibiotic, two had vaginal moniliasis developing right
after their menstrual period; one had intestinal and cutaneous
manifestations (perineal and crural) developing also after broad-spectrum
antibiotic therapy. All the four patients had exacerbation of the urticaria
while undergoing the monilia infection. After 1-2 weeks of elimination
diet, each patient was challenged with yeasts-containing foods (bread,
buns, sausages, beer, wines, grapes, cheese, vinegar, tomato catsup).
Twenty-five patients (71%) of the group who positively reacted with a Type
I/III reaction when tested with Candida antigen, showed a positive
provocation test (reappearance of urticaria) and twenty patients (69%) of
the group who reacted with Saccharomyces had a positive challenge test...

14. Ann Allergy 1987 Jul;59(1):48-51 
Chronic asthma and rhinitis due to Candida albicans, epidermophyton, and
trichophyton.
Gumowski P, Lech B, Chaves I, Girard JP

Asthma and rhinitis due to Candida albicans is well known. Trichophyton and
Epidermophyton are not usually considered as causal agents for these
diseases. During the years 1982 and 1983 all of the cases of chronic asthma
or rhinitis exhibiting a positive immediate skin response (greater than or
equal to 10 mm) to one of these three antigens were selected for this study
(60 asthma and 75 rhinitis). They all went through nasal and bronchial
provocation tests with the specific antigen. Late reactions were also
registered. A RAST was performed in some of the patients reacting to
Candida albicans. Following inhalation challenge with antigens, an
immediate response was obtained in 91 cases (asthma 30, rhinitis 51). A
dual response was observed in 17 cases of asthma and in 13 cases of
rhinitis. A RAST-Candida albicans was done in 64 cases. Results were
positive in 52 patients. In 46 cases there was a correlation between the
RAST and the provocation tests. Hyposensitization treatment was given to 92
patients. After 2 years of treatment, a good to excellent response could be
observed in almost 60% of the treated cases. A rough estimation of the
incidence of immediate bronchial and nasal hypersensitivity among patients
with chronic asthma and rhinitis to the three yeasts gives the approximate
figure of 8% to 10%.

15. Infect Immun 1983 Oct;42(1):285-92  Effect of strain of Staphylococcus
aureus on synergism with Candida albicans resulting in mouse mortality and
morbidity.
Carlson E

16. Am J Gastroenterol 1980 Apr;73(4):305-9 
Peritonitis in patients with liver disease and ascites. Use of Candida
albicans as a microbiological clue in differential diagnosis.
Wormser GP, Leber G, Tatz J, Reiner M, Kurtz R

Peritonitis in patients with pre-existing liver disease and ascites may be
secondary to a local abdominal condition which potentially requires surgery
for cure, or alternatively, may be spontaneous in origin. For the latter,
antimicrobials are therapeutic while surgery is contraindicated. An easily
accessible and important clue for distinguishing these forms of peritonitis
may be found in the microbiology of ascitic fluid. Visualization on gram
stain smear or recovery on culture of multiple organisms and/or anaerobes
favors local abdominal disease over spontaneous peritonitis. The presence
of Candida species in the ascitic fluid of such patients, although less
common, is highly significant. In the absence of peritoneal dialysis,
recent abdominal surgery, or risk factors for disseminated candidiasis, the
isolation of Candida suggests specifically gastrointestinal perforation.

17. Neuropsychobiology 1995;31(2):53-7   
DR-positive T cells in autism: association with decreased plasma levels of
the complement C4B protein.  
Warren RP et al.

18. Arch Pediatr Adolesc Med 1994 Feb;148(2):180-3   
Decreased plasma concentrations of the C4B complement protein in autism. 
Warren RP et al.

19. Clin Exp Immunol 1991 Mar;83(3):438-40   
Increased frequency of the null allele at the complement C4b locus in
autism. 
Warren RP, Singh VK et al.

20. Murphy JW et al. Type 1 and type 2 cytokines: from basic science to
fungal infections. Medical Mycology 1998 36:Supp 1:109-118. [an excellent
review!]

21. Romani L. Immunity to Candia albicans: Th1, Th2 cells and beyond. Curr
Opin Microbio 1999 2:363-7. [an excellent review]

22. Murphy JW. Cell-mediated immunity and medically related fungi. Ch 36
in: Effects of Microbes on the Immune System; editors Cunningham MW,
Fujinami RS; Lippincott Williams & Wilkins, Philadelphia, 2000. [an
excellent review]

23. J Neuroimmunol 1998 May 1;85(1):106-9 
Th1- and Th2-like cytokines in CD4+ and CD8+ T cells in autism.
Gupta S, Aggarwal S, Rashanravan B, Lee T
Department of Medicine, University of California, Irvine 92697-4075, USA.
sgupta@uci.edu

Th1-like (IL-2, IFN-gamma) and Th2-like (IL-4, IL-6, and IL-10) cytokines
were examined in CD4+ and CD8+ T cells in children with autism.
Intracellular cytokines were measured using specific antibodies to various
cytokines and anti-CD4 or anti-CD8 monoclonal antibodies by FACScan. 
     Proportions of IFN-gamma+CD4+ T cells and IL-2+CD4+ T cells
     (Th1), and IFN-gamma+CD8+ and IL-2+CD8+ T cells (TC1) were
     significantly lower in autistic children as compared to healthy
     controls. 
In contrast, IL-4+CD4+ T cells (Th2) and IL-4+CD8+ T cells (TC2) were
significantly increased in autism. 
     The proportions of IL-6+ CD4+, IL-6+CD8+ and IL-10+CD4+,
     IL-10+CD8+ T cells were comparable in autism and control group.
     These data suggest that an imbalance of Th1- and Th2-like
     cytokines in autism may play a role in the pathogenesis of
     autism.