Neonatal with a cabbage smell: and the background of how many 'lesser' health problems are 'discovered'

A lot of health problems depend on twists of fate and luck, rather than any organised route of deduction, to get established. It's interesting to compare this case, to the establishment of trimethylaminuria as a metabolic body odor diagnosis.

In this case, the neonatal had encephalopathy, and only later developed a "cabbage-odor". Through a thorough testing of urine organic acids which involved special equipment to detect volatile sulfur compounds, they discovered high levels of hydrogen sulfide (the chemical in stink bombs) and methanethiol. The baby went on to fully recover and their theory is that it wasn't the cause of the encephalopathy but may have contributed. They suggest the smell was caused by overgrowth of some abnormal colonic bacteria. This was published in 1997 (a pediatric case), but somehow doesn't seem to have been picked up on.

neonatal with a "cabbage-odor" : pubmed case study 1997

Full paper of 'neonatal with a cabbage odor' case study

Similarly, trimethylaminuria seems to have first been reported by a pediatric unit(?). The 6 year old girl had serious health problems from birth.

For whatever reason, today the TMAU urine test is likely the only Volatile Organic Acid test offered to metabolic body odor sufferers (if they are lucky enough to find a tester), although dimethylglycinuria also has seem to have caught the attention of a few TMAU testers, basing it on one paper in pubmed.

The OMIM entry for TMAU gives the following quote to the 'founding' of TMAU as a diagnosis

Humbert et al. (1970) first used the terms trimethylaminuria and fish-odor syndrome to describe a 6-year-old girl who intermittently had a fishy odor. She also had multiple pulmonary infections beginning in the neonatal period, the clinical stigmata of Turner syndrome but normal karyotype, splenomegaly, anemia, and neutropenia. Her urine contained increased amounts of TMA. In the same patient, Humbert et al. (1971) found defective membrane function in platelets, neutrophils, and red cells, and Higgins et al. (1972) found deficiency of trimethylamine oxidase by liver biopsy. Calvert (1973) noted that the features in the patient of Humbert et al. (1970) were those of Noonan syndrome (163950). He studied a clinically identical patient but found no trimethylaminuria with or without loading with trimethylamine. Witt et al. (1988) included the patient of Humbert et al. (1970) in their series of cases of Noonan syndrome with bleeding diathesis.

OMIM entry for trimethylaminuria

Humbert et al seem to have a connection with the University of Colarado health sciences center, which may exlain Dr Fennesseys connection with TMAU. Dr Fennesseys lab is by far the biggest TMAU urine tester for Americans who have tested so far. He is also a graduate friend of Dr Preti of Monell Chemical Senses Center.

If society took a more thorough look at body odor and halitosis, you have to wonder what they would discover and in what time ? You would think a starting point would be a testing of all malodourous volatile organic compounds in urine, rather than strictly looking for a few. FMO3 deals with many sulfides and amines, many of which are smelly. Now with the internet, the search for answers can be 'patient' led, both in lobbying the established system, and if need be then looking for answers in an organised way themselves, rather than waiting for random answers from pubmed, in the hope someone will post a study.

Interesting quotes from the mentioned paper:

A baby presenting with a neurological disturbance and an abnormal body odour must be
investigated urgently for a possible inherited metabolic disorder. Tests were all negative in the case reported. Eventually methanethiol and hydrogen sulphide were identified as the cause of the malodour.They were probably produced in grossly increased amounts in the colon by bacterial fermentation due to very unusual circumstances.

On day 12 there was an abnormal smell around his incubator which pervaded the nursery, and for the next three days his urine had asharp, pungent, cabbage-like smell. This then disappeared.Until day 13 he was maintained on nil bymouth, fed parenterally, and given intravenous antibiotics (metronidazole, flucloxacillin, andpiperacillin, later changed to ampicillin). By day 18 he was feeding and handling normally. At 11 months of age he was developing and growing normally. He has recurrent wheeze as does his 3 year old brother.

Attempts toidentify the malodorous compounds in urineby headspace gas chromatography-mass spectrometry (GC-MS) using standard hospital equipment failed. However, using GC with a dedicated sulphur chemiluminescence detector
(Sievers 350B detector), large amounts of methanethiol (methylmercaptan, CH3SH) and
hydrogen sulphide (H2S) were found (fig 1).

There are three sources of methanethiol in the body. It is produced by the liver during degradation of methionine by the transamination pathway. Production is increased after methio-
nine loading, in patients with hypermethioninaemia due to an inherited defect and in liver
disease (controversial). Secondly, it is produced from sulphur amino acids by fermentative bacteria in the colon, often with H2S and possibly ammonia. Thirdly, it is formed within
intestinal cells by methylation of H2S absorbed from the colon. Increased liver production is unlikely here and would not have accounted for the H2S found. The compounds were probably produced in the colon. Bleeding into the bowel would have supplied sulphur amino acids, and
use of broad spectrum antibiotics may have led to unusual colonisation by a fermentative
organism.

The compounds were probably present in the urine because of faecal contamination, but no bacteria were cultured from the malodorous urine collected on day 14. The alternative is that they were absorbed from the colon (demonstrated in rats) and then excreted. The problem with this explanation is that absorbed methanethiol is converted rapidly to disulphides and sulphate by the liver and perhaps blood cells. If absorbed compounds were the source they would have to have escaped hepatic detoxification. The only reported patient with methanethiol in urine had
massive hepatic necrosis. In the case reported here liver function tests were normal. On the
other hand, closure of the ductus venosus could have been delayed, with diversion of por-
tal blood from the liver to the systemic circulation.

The baby’s encephalopathy was almost certainly caused by a transient metabolic
abnormality. There was no serious hypoxicischaemic episode, infection, or inherited
biochemical defect to explain it. Hyperammonaemia (from the gut?) cannot be excluded as
plasma ammonium measurement was delayeduntil day 14 and was then near our upper
acceptable limit. Both H2S and methanethiol are neurotoxic. In rats they cause coma and
methanethiol may precipitate respiratory failure. Brain toxicity of methanethiol is
enhanced by ammonia and small amounts of octanoic acid, indicating synergy between these
compounds. By the time the odour was noticed, the encephalopathy was well advanced, suggesting that the thiol compounds were not primary causative agents. They mayhave contributed, perhaps in synergy with ammonia, if high blood concentrations were
achieved.

Few clinical laboratories have instruments to detect volatile sulphur compounds. A
screening test for H2S in gas from malodorousfluid (lead acetate strip, BDH-Merck, Poo-
le,UK) would help to exclude an inborn error.