Conflicts of interest

Approval of minutes Jan 2018 conference call

• Reactive arthritis and modeling extraarticular manifestations using simple co-occurrence
• Test of allergic disorder model as pathologic structure
• Sepsis

  • Sepsis
    1. Agreement to add dysregulated host response as a pathological process.
    2. Agreement not to add pathological process infectious process which would result in sepsis being defined as organ dysfunction syndrome co-occurrent and due to infectious disease.

• Test of device complications model

  • Device complications
    Problems with the device itself should be a finding and not a disorder. This would allow some rearrangement of the current device problem findings. The modleing structure would be to use the INTERPRETS/HAS INTERPRETATION pair to define the findings.
    Should also create a more specific "device failure" to segregate from general external equipment failure.
    desire to see more examples for each of the three patterns.

6

On the ICD-11 MSAC call recently, a discussion ensured about the recent changes to nomenclature for Amyloidosis, with an emphasis on etiology (i.e. the type of amyloid) with secondary interest in the anatomical location of the amyloid deposition. This is contrary to the current way SNOMED classifies amyloidosis, which focuses on the site of deposition as opposed to detailed information about the type of amyloid.

WHO description:

Amyloidosis is a vast group of diseases defined by the presence of insoluble protein deposits in tissues. Its diagnosis is based on histological findings. Amyloidoses are classified according to clinical signs and biochemical type of amyloid protein involved. Most amyloidoses are multisystemic, 'generalized' or 'diffuse'. There are a few forms of localized amylosis. The most frequent forms are AL amyloidosis (immunoglobulins), AA (inflammatory), and ATTR (transthyretin accumulation).

Reference for amyloidosis nomenclature is here.

Discussion points:

1) The current subhierarchy <<17602002 |Amyloidosis (disorder)| is mostly primitive and does not go into much detail about the biochemical characteristics of the amyloid protein. Do we want to add the specific subtypes of amyloid?

2) Do we want to align the SNOMED CT amyloidosis content to the ICD-11 approach? What is the clinical importance? Most general clinical references emphasize the underlying origin of the amyloid (i.e. genetic, inflammation, dialysis).

Common pattern in classifications such as ICD. Currently all are primitive in SNOMED CT.

One potential modeling pattern proposed is the use of the Situation model with one "known present" relationship group and one "known absent" relationship group.

The problem with specific negation is that it is silent about other clinical aspects that may be of significance.

What is the purpose of calling out one specific clinical manifestation?

Comments solicited from, CMAG: Use of concepts representing the presence of a disorder without a second disorder

We received a comment from a dutch lexographer:

Dear fellow terminologist(s),

I am the Dutch medical linguist currently in charge of checking translations of SNOMED terms into Dutch (as for the Netherlands, not for Belgium) on morphosyntactical rules. In 2015 I translated the IHTSDO translation guidelines into Dutch as an assignment by Nictiz, the Dutch release centre.

It occurs to me that in compound adjectives in many SNOMED terms, the dash has been left out:
– pacing induced cardiomyopathy = ‘a sentence in past tense stating that …’?
§ where I expect: pacing-induced cardiomyopathy = cardiomyopathy induced by pacing
– left sided atrium connecting to both ventricles > ‘lefties sitting next to…’?
§ where I expect: left-sided atrium

This will unintentionally render a collocation into a sentence, as in many cases the past participle is a homograph of the verb in past tense. In most cases however, the term will be interpreted correctly anyhow.

Why does SNOMED not follow commonly taught spelling rules in English? I do know that in informal American English this compounding dash has become somewhat uncommon. Likewise, the adverbial suffix ‑ly was abolished in the USA already a while ago. Possibly this dash will join its fate. Must SNOMED anticipate this? I feel that a mere spelling inaccuracy should not be a reason for terminologists to embrace it.

Likewise, the ISO 704 norm for terminology instructs that a term should not be capitalized without a reason. In Dutch we will spell stomach and not Stomach. As a lexicographer I come across this irrational, somewhat ‘American’ typesetting custom in a very few, mostly obsolete medical glossaries only. Has SNOMED International never considered running some semi-conditional routine for replacing an initial letter in upper case where not required with the letter in lower case?

Has SNOMED International been spending any thoughts on these two orthographical matters? I hope that you will be willing to share your thoughts on this with me. It will be interesting to be able to learn from each other’s expertise and practice!

No testing of options for this item has been performed since the last meeting. Issues still remaining:

• Eliminating the soft default (yes or no)
• Creating unspecified SPECIMEN SOURCE concepts only where both patient-oriented and non-patient specimens are required.
• Resolving issues with specimen sources that are both patient and non-patient oriented (i.e. autologous blood products)
• Resolution of non-patient subtypes under unspecified SPECIMEN SOURCE (i.e soft default) concepts

• There are existing "Acquired X (morphologic abnormality)" concepts, but these are very much analogous to the "Congenital X" morphologies that we are trying hard to get rid of. 
• "Acquired" and "Congenital" are not morphologies, but timeframes.  We do not have a way of denoting "All periods of life after birth" like we do for "Congenital".  If we did, then we could create a fully defined concept grouper of "Acquired disorder", which would subsume all concepts that had any OCCURRENCE value later than "At birth", but then it would require that all acquired disorders have a valid OCCURRENCE relationship.
• This approach might also open the door that all disorders that are not specifically “Congenital” have an OCCURRENCE relationship stating that it is required, which seems to be “overmodeling”.  While we can use the "Acquired deformity" morphology concepts currently, due to the lack of many useful subtypes of "Acquired X" morphologies, it would only be a partial solution. 
• One potential solution is to create a primitive grouper of "Acquired disorder" and then using that as the proximal primitive parent, adding the necessary relationships to make acquired disorders defined.  It is a kludge, but it would allow for full definition.

Update: A grouper "period of life" term encompassing all stages of life (Postnatal (qualifier value)) after birth was created. Over 100 concepts with the string "Acquired" were reviewed and fully defined using the OCCURRENCE attribute. There were no adverse impacts from this initial test.

One conditional issue relates to the ability to define terms with the string "juvenile". The definition of juvenile differs in age ranges from jurisdiction to jurisdiction. Likewise the definitions of age ranges for "childhood" and "adolescent". There is an inactive concept 282035009 - Juvenile (qualifier value) that was once a subtype of "Period of life", but was inactivated as duplicate to 59223006 - Juvenile (finding).

The process to progress this needs to be determined.

2017-11-03: A related tracker exists: PCP-71. The work related to this item will be linked to that tracker.

Issue identified during testing was the perceived need for the concept "juvenile", which is an inactive concept.

Concern about how many concepts will be affected. Will all concepts that are known to be acquired have this attribute added? No, only concepts that need a differentiation between a congenital and acquired form.

It may not even be necessary to have as many periods of life as we currently have.

While the results of testing are encouraging, it is better to have another attribute that can be role grouped than to create a primitive parent to be used as an IS A due to the advantages that come out of classification.

The current testing has resulted in very few changes to the existing taxonomy, but makes the content more maintainable.

Juvenile concepts may still be needed, but can be put off for later consideration (can be modeled with postnatal until then).