A person who suffered from Multiple Chemical Sensitivity(MCS) for many years before it progressed into Mast Cell Syndrome(MCAS) forward an article, “Chemical Intolerance and Mast Cell Activation: A Suspicious Synchronicity“, 2023. At the same time, my understanding of the complex nature of the microbiome also made a leap forward. For those interested, see these three very technical posts:

• Using Mean and Standard Deviation for Bacteria is Inappropriate.
• Significant Bacteria and Their Thresholds – Part 1
• Significant Bacteria and Their Thresholds – Part 2

I decided to look at Mast Cell Activation Syndrome again in the hope of gaining insight into treatment possibilities.

The samples being using are donated by readers from various labs with symptoms being self-declared. Symptoms may not agree with clinical definitions. All of the data is freely available for those that are highly skilled with statistics at Citizen Science Distribution.

First, MCS::MCAS

	With MCAS	With MCS	WITH MCAS and MCS	With Any Symptoms
Count	305	219	62	3025
Percentage	10%	7.2%	2%

• If MCAS and MCS are independent, we would expect 10% x 7.2% or 0.72% overall. We have 3 times more than expected.
• The chi-square statistic is 19.3693. The p-value is .000011. VERY SIGNIFICANT CONNECTION.

This disagrees on face value with the reported “Our outcomes confirm the previously published study where the majority of MCAS patients also have CI. ” For this to be true, With MCAS and MCS would be > 150. Differences in methodology may be the cause for this disagreement, but regardless, we see that a person with MCAS is around three times more likely to have had MCS. I read this as suggesting that MCS is a precursor for a class of MCAS. Having MCS prior is not required to developing MCAS; but having MCS means the odds of getting MCAS are much increased.

Looking at Bacterium

I am going to use samples processed through Biomesight only because it is the largest sample set.

For MCS

The table below is filtered to those with P < 0.001 at the genus level with the highest first (P < 5.19132E-05).

Name	Direction
Actinocatenispora	Low
Hathewaya	High
Thauera	Low
Devosia	Low
Thiocapsa	Low
Deferribacter	Low
Viridibacillus	Low
Candidatus Tammella	Low
Coraliomargarita	Low
Geothrix	Low
Desulfosporosinus	Low
Glutamicibacter	Low
Denitratisoma	Low
Catenibacterium	Low
Desulforamulus	Low
Geobacter	Low
Neisseria	Low
Nonomuraea	Low
Agromyces	Low
Anaerotruncus	High
Oenococcus	Low
Saccharopolyspora	Low
Lentibacillus	Low

MCAS

The table below is filtered to those with P < 0.001 at the genus level with the highest first (P < 6.25726E-07).

Name	Direction
Emticicia	Low
Pseudoramibacter	Low
Parascardovia	Low
Rickettsia	Low
Calothrix	Low
Nonomuraea	Low
Marinospirillum	Low
Azospirillum	Low
Neisseria	Low
Viridibacillus	Low
Helicobacter	Low
Peptacetobacter	Low
Nitrosococcus	Low
Avibacterium	Low
Schaalia	Low
Propionigenium	Low
Flammeovirga	Low
Oligella	Low
Erysipelothrix	High
Geobacter	Low
Catenibacterium	Low
Pontibacter	Low
Isoalcanivorax	Low
Faecalitalea	Low
Jonesia	Low
Thalassospira	Low
Amedibacillus	High
Arthrobacter	Low
Hathewaya	High

MCAS and MCS

The table below is filtered to those with P < 0.001 with the highest first (P < 1.85255E-05). The sample size is much smaller, so fewer items were significant, hence all ranks are shown.

Name	Rank	Direction
Chloroflexota	phylum	Low
Anaerolineae	class	Low
Eggerthella sinensis	species	Low
Desulfofundulus	genus	Low

Probiotic Remedies?

Because there are simply no published studies on most of the above bacterium, I went over to the R2 site to compute candidate probiotics. Note: Some of these probiotics are still in development or available only in some countries.

MCS

I enclosed the full list because you want to make sure NOT to take any with a Net being negative. Also, the safest are those with BAD being Zero (0)

Tax_Name	Tax_Rank	Good	Bad	Net
Christensenella minuta	species	194	29	165
Aspergillus oryzae	species	138	0	138
Faecalibacterium prausnitzii	species	185	78	107
Anaerobutyricum hallii	species	162	58	104
Enterococcus faecium	species	124	37	87
Blautia hansenii	species	122	37	85
Lactiplantibacillus plantarum	species	64	0	64
Roseburia intestinalis	species	118	60	58
Bifidobacterium catenulatum	species	53	0	53
Priestia megaterium	species	47	0	47
Bacillus pumilus	species	43	0	43
Bacteroides thetaiotaomicron	species	37	0	37
Latilactobacillus sakei	species	37	0	37
Bifidobacterium breve	species	32	0	32
Levilactobacillus brevis	species	31	0	31
Parabacteroides distasonis	species	31	0	31
Parabacteroides goldsteinii	species	54	28	26
Pediococcus pentosaceus	species	25	0	25
Limosilactobacillus reuteri	species	23	0	23
Shouchella clausii	species	23	0	23
Lactiplantibacillus argentoratensis	species	23	0	23
Bifidobacterium longum	species	20	0	20
Bifidobacterium adolescentis	species	39	21	18
Blautia wexlerae	species	74	57	17
Lactococcus cremoris	species	36	21	15
Enterococcus faecalis	species	14	0	14
Bifidobacterium pseudocatenulatum	species	13	0	13
Limosilactobacillus vaginalis	species	12	0	12
Lactobacillus kefiranofaciens	species	12	0	12
Lactococcus lactis	species	11	0	11
Clostridium beijerinckii	species	11	0	11
Streptococcus thermophilus	species	10	0	10
Leuconostoc mesenteroides	species	10	0	10
Segatella copri	species	37	29	8
Phocaeicola coprocola	species	27	21	6
Bacillus subtilis	species	26	21	5
Lactobacillus crispatus	species	11	11	0
Lactiplantibacillus pentosus	species	0	11	-11
Bacteroides uniformis	species	20	32	-12
Limosilactobacillus mucosae	species	0	14	-14
Lacticaseibacillus casei	species	0	17	-17
Bacillus cereus	species	33	54	-21
Bacillus licheniformis	species	0	22	-22
Ligilactobacillus salivarius	species	11	41	-30
Lactobacillus jensenii	species	0	36	-36
Akkermansia muciniphila	species	12	50	-38

MCAS

Tax_Name	Tax_Rank	Good	Bad	Net
Christensenella minuta	species	83	0	83
Aspergillus oryzae	species	68	0	68
Enterococcus faecium	species	58	0	58
Faecalibacterium prausnitzii	species	53	0	53
Roseburia intestinalis	species	53	0	53
Anaerobutyricum hallii	species	51	0	51
Blautia wexlerae	species	44	0	44
Bacillus pumilus	species	28	0	28
Priestia megaterium	species	27	0	27
Levilactobacillus brevis	species	25	0	25
Latilactobacillus sakei	species	25	0	25
Lactiplantibacillus argentoratensis	species	23	0	23
Blautia hansenii	species	22	0	22
Limosilactobacillus fermentum	species	21	0	21
Shouchella clausii	species	20	0	20
Limosilactobacillus reuteri	species	18	0	18
Lactiplantibacillus plantarum	species	17	0	17
Bacillus subtilis	species	16	0	16
Bifidobacterium animalis	species	15	0	15
Bifidobacterium animalis subsp. lactis	subspecies	15	0	15
Lactobacillus acidophilus	species	14	0	14
Clostridium butyricum	species	13	0	13
Bifidobacterium adolescentis	species	12	0	12
Ligilactobacillus salivarius	species	11	0	11
Hafnia alvei	species	11	0	11
Bacteroides uniformis	species	0	15	-15
Lacticaseibacillus rhamnosus	species	0	16	-16
Bacteroides fragilis	species	0	23	-23

Bottom Line

The most confidence is to work on probiotics only with the following being strongly recommended.

• Aspergillus oryzae
• Enterococcus faecium
• Bacillus pumilus
• Bacillus subtilis
• Lactiplantibacillus plantarum a.k.a. Lactobacillus plantarum
• Bifidobacterium catenulatum
• Bifidobacterium breve
• Levilactobacillus brevis a.k.a. Lactobacillus brevis
• Latilactobacillus sakei a.k.a. Lactobacillus sakei
• Limosilactobacillus reuteri a.k.a. Lactobacillus reuteri
• Shouchella clausii a.k.a. Bacillus Clausii
• Lactobacillus acidophilus
• Ligilactobacillus salivarius a.k.a. Lactobacillus salivarius

The top one for both is Aspergillus oryzae. This is likely unfamiliar to most people. It is also known as Shirayuri Koji. It is available on Amazon, not as a probiotic but cooking additive!! It is in Koji Rice. It is also solid as strong wakamoto w

With Tariffs ordering from Japan can get expensive, https://www.yami.com/ ships from the US, so no tariffs costs!

CAUTION: This is based on modelled data and not verified by clinical studies. IMHO, it is likely a superior set of suggestions than other more “conventional” approaches.