EmailAllergy T78.4
Publication Date: September 2015
ICD 10 AM Edition: Eighth edition
Query Number: 2948
VICC #2351 Category T78 was retired 30/06/2013. Can VICC please advise if the advice is still applicable?
Response
This query was originally published in the 2014-15 December VICC queries database release as follows:
VICC advises that the advice provided in #2351 Category T78 is still applicable in Eighth edition and is reproduced below with minor wording amendments:
Query:
Please clarify application/interpretation of the Note in category T78
T78 Adverse effects, not elsewhere classified
Note: This category is to be used to identify the effects, not elsewhere classifiable, of unknown, undetermined or ill-defined causes. For multiple coding purposes this category may be used as an additional code to identify the effects of conditions classified elsewhere.
Excludes: complications of surgical and medical care NEC (T80-T88)
Is it correct to interpret this note to mean that if the nature of the adverse effect is documented, that a code for the effect should be assigned, before a T78 code (specifically T78.0, T78.1, T78.2 and T78.3)? Is it optional to assign T78 as an additional diagnosis?
What does the reference to 'unknown, undetermined or ill-defined causes' mean? Does this note only apply if the cause is unknown, undetermined or ill-defined? For example, if the cause of the allergic reaction is known such as seafood, is it appropriate to assume this note does not apply?
Patient diagnosed with lip swelling as a result of an allergic reaction to seafood. How should this be coded?
Patient presents with swelling of the lips, face and tongue. Discharge summary states angioedema as the principal diagnosis. Should T78.3 be assigned as principal diagnosis or R22.0 Localised swelling, mass and lump, head?
Response:
In response to your questions, the VICC advises that it is correct to interpret the note at Category T78 to mean that if the nature of the adverse effect is documented, a code for the effect should be assigned before a T78 code and that it is optional to assign T78 as an additional diagnosis code.
The reference to 'unknown, undetermined or ill-defined causes' is applicable to countries with single condition coding where for example, the adverse effect or allergy was known but not the cause so only a code from the T78 range would be assigned. Therefore this note is not relevant in Australia.
For scenario one where the patient diagnosed with lip swelling as a result of an allergic reaction to seafood assign:
R22.9 Localised swelling, mass and lump, unspecified
T78.1 Other adverse food reactions, not elsewhere classified
Y57.9 Drug or medicament, unspecified
For scenario two, the VICC considers that the only codes required are T78.3 Angioneurotic oedema and the external cause codes as the discharge summary states angioedema as the principal diagnosis.[end of response]
Following publication of the September 2015 Coding Rules the original response is superseded by the following advice under heading Coding of allergic reactions NOS and anaphylactic reactions:
Q:
How should allergic reactions not otherwise specified (NOS) and anaphylactic reactions be coded? Should symptom codes be assigned for allergic reactions?
A:
The correct code assignment for allergic reactions NOS and anaphylactic reactions are outlined below.
Allergic reaction NOS:
T78.4 Allergy, unspecified following the guidelines in ACS 2004 Allergic reaction NOS and the index pathway:
Allergy, allergic (reaction) T78.4
Allergic reaction NOS to food:
T78.1 Other adverse food reactions, not elsewhere classified following the index pathway:
Allergy, allergic (reaction)
- food (any) (ingested) NEC T78.1
Anaphylaxis due to food:
T78.0 Anaphylactic shock due to adverse food reaction following the index pathway:
Allergy, allergic (reaction)
- food (any) (ingested) NEC
- - anaphylactic shock T78.0
When assigning a code classified to category T63 Toxic effect of contact with venomous animals additional codes should be assigned for any associated allergic reaction as per the instructional note at this category.
Symptoms such as wheeze, urticaria and swelling should not be coded when a diagnosis of allergic reaction or anaphylaxis has been established unless the symptom is significant in its own right and treated independently of the allergic reaction following the guidelines in ACS 1802 Signs and symptoms.
Assign external cause codes as appropriate.
VICC advises that the advice provided in #2351 Category T78 is still applicable in Eighth edition and is reproduced below with minor wording amendments:
Query:
Please clarify application/interpretation of the Note in category T78
T78 Adverse effects, not elsewhere classified
Note: This category is to be used to identify the effects, not elsewhere classifiable, of unknown, undetermined or ill-defined causes. For multiple coding purposes this category may be used as an additional code to identify the effects of conditions classified elsewhere.
Excludes: complications of surgical and medical care NEC (T80-T88)
Is it correct to interpret this note to mean that if the nature of the adverse effect is documented, that a code for the effect should be assigned, before a T78 code (specifically T78.0, T78.1, T78.2 and T78.3)? Is it optional to assign T78 as an additional diagnosis?
What does the reference to 'unknown, undetermined or ill-defined causes' mean? Does this note only apply if the cause is unknown, undetermined or ill-defined? For example, if the cause of the allergic reaction is known such as seafood, is it appropriate to assume this note does not apply?
Patient diagnosed with lip swelling as a result of an allergic reaction to seafood. How should this be coded?
Patient presents with swelling of the lips, face and tongue. Discharge summary states angioedema as the principal diagnosis. Should T78.3 be assigned as principal diagnosis or R22.0 Localised swelling, mass and lump, head?
Response:
In response to your questions, the VICC advises that it is correct to interpret the note at Category T78 to mean that if the nature of the adverse effect is documented, a code for the effect should be assigned before a T78 code and that it is optional to assign T78 as an additional diagnosis code.
The reference to 'unknown, undetermined or ill-defined causes' is applicable to countries with single condition coding where for example, the adverse effect or allergy was known but not the cause so only a code from the T78 range would be assigned. Therefore this note is not relevant in Australia.
For scenario one where the patient diagnosed with lip swelling as a result of an allergic reaction to seafood assign:
R22.9 Localised swelling, mass and lump, unspecified
T78.1 Other adverse food reactions, not elsewhere classified
Y57.9 Drug or medicament, unspecified
For scenario two, the VICC considers that the only codes required are T78.3 Angioneurotic oedema and the external cause codes as the discharge summary states angioedema as the principal diagnosis.[end of response]
Following publication of the September 2015 Coding Rules the original response is superseded by the following advice under heading Coding of allergic reactions NOS and anaphylactic reactions:
Q:
How should allergic reactions not otherwise specified (NOS) and anaphylactic reactions be coded? Should symptom codes be assigned for allergic reactions?
A:
The correct code assignment for allergic reactions NOS and anaphylactic reactions are outlined below.
Allergic reaction NOS:
T78.4 Allergy, unspecified following the guidelines in ACS 2004 Allergic reaction NOS and the index pathway:
Allergy, allergic (reaction) T78.4
Allergic reaction NOS to food:
T78.1 Other adverse food reactions, not elsewhere classified following the index pathway:
Allergy, allergic (reaction)
- food (any) (ingested) NEC T78.1
Anaphylaxis due to food:
T78.0 Anaphylactic shock due to adverse food reaction following the index pathway:
Allergy, allergic (reaction)
- food (any) (ingested) NEC
- - anaphylactic shock T78.0
When assigning a code classified to category T63 Toxic effect of contact with venomous animals additional codes should be assigned for any associated allergic reaction as per the instructional note at this category.
Symptoms such as wheeze, urticaria and swelling should not be coded when a diagnosis of allergic reaction or anaphylaxis has been established unless the symptom is significant in its own right and treated independently of the allergic reaction following the guidelines in ACS 1802 Signs and symptoms.
Assign external cause codes as appropriate.
