LOINC Codes for Lab Tests

[Melissa Armao]

We are trying to ascertain what Adult LOINC codes to mine for in our data, in an effort to accurately capture the values requested by DOH.  We have come up with this spreadsheet, and are wondering if anyone would be interested in reviewing the lists we have created with a clinical eye?  I have attached them here, and am happy to answer any questions.  Thank you all in advance!

Melissa Bauer

[Gregory Briddick, Jr.]

OK.  Let's start with the Lactate list of LOINC codes. 

LOINC codes are a structured ontological language which groups similar labs together based on their characteristics.  When we are talking about Lactate specifically, we need to define the two general characteristics which are pertinent to capturing the correct Lactate codes.  These are PROPERTY variables within the LOINC dataset, with the two pertinent properties being SCnc and MCnc.  The difference between SCnc and Mcnc is the measurement type, with MCnc being a measurement of the Mass Concentration and SCnc being the measurement of the Substance Concentration.  MCnc is not typically used in the US for electrolyte measurements, and is the measurement of the lab based on mass over volume, such as mg/dl.  SCnc is what most laboratories measure lactate as, as a measurement of moles present in the solute, reported as mmols/L.  See this Knowledge Base page for LOINC:  https://loinc.org/kb/faq/content/#what-is-the-difference-between-mass-concentration-mcnc-and-substance-concentration-scnc

Once we define what our laboratories are using (MCnc vs SCnc), we then need to capture the correct System and Class. 

For the System, we are focusing only on blood, serum, and plasma levels.  These should be denoted as BldV, BldA, PlasA, PlasV, Ser/Plas.  Most lactates are collected in either fluoride or lithium tubes, which are both plasma collection processes.  Blood levels are to capture the second most common route of collection which is ABG/VBG collections (BldA/BldV). 

Class is the timing of the test.  For Lactates, we are performing spot checks for lactate levels, and not using trended values post incident (or over a duration of time like a 24hr urine collection).  CHEM denotes that it is a spot check, where CHAL denoted that the lab occurs after a challenge event (you will see lactates collected after exercise like 2hr post exercise, etc.).  See this Knowledge Base page for LOINC:   https://loinc.org/kb/users-guide/classes/#laboratory-term-classes

So, here are the codes which we use in my institution:

2518-9         Lactate      SCnc        BldA               CHEM    

2519-7         Lactate      SCnc        BldV               CHEM    

2524-7         Lactate      SCnc        Ser/Plas        CHEM    

If your institution utilizes MCnc based Lactate (mg/dl, not mmol/L) then these should be the codes you are looking for:

30242-2       Lactate      MCnc        BldA               CHEM    

30241-4       Lactate      MCnc        BldV               CHEM    

14118-4       Lactate      MCnc        Ser/Plas        CHEM  

You may see the following codes in rare instances:

32132-3       Lactate      SCnc         PlasA             CHEM    

32133-1       Lactate      SCnc         PlasV             CHEM    

35245-0       Lactate      MSCnc     Ser/Plas        CHEM  (This code reports both mmol/L and mg/dl values, which seems problematic since you would need to determine which format is being reported in order to facilitate the format for NYSDOH)

There are a few other Systems which I haven't seen in the clinical setting, but may exist in your institution.  These would include:

Capillary blood (BldC)

SCnc      19239-3

MCnc     51829-0

and Whole Blood (Bld)

SCnc      32693-4

MCnc     59032-3

The remainder of the systems aren't applicable to most instances of Sepsis:  Urine (Urine), Bodily Fluids (Body fld), CSF (CSF), Gastric Fluid (Gast fld), Pleural Fluid (Plr fld), Synovial Fluid (Sync fld), Cord Blood (BldCo), and Cord/Fetal blood (BldC^Fetus).

I hope that this helps to understand the layout of LOINC and how to read some of the language.

Thanks,

Gregory RN

[Gregory Briddick, Jr.]

OK.  Let's talk about CHG tests for pregnancy.

CHG tests can be used for many things, outside of pregnancy (such as certain cancer monitoring), which can cloud the use of hCG tests to determine pregnancies.  Most pregnancy tests done in the ED are POCT tests, including those which are lab sends.  These are often resulted by a defined threshold for pos/neg, vs returning a actual measurement of the hCG levels (Quantitative vs. Qualitative testing).  The most common of these are Urine samples, with Ser/Plas levels being secondary.  There are also a number of different ways to measure hCG, including intact hCG (the only active form), alpha-subunit, beta-subunit, nicked hCG, Beta-Core hCG, and hyperglycosylated hCG. 

https://doi.org/10.1093/humrep/deh702

https://www.aacc.org/science-and-research/clinical-chemistry-trainee-council/trainee-council-in-english/pearls-of-laboratory-medicine/2011/human-chorionic-gonadotropin

If the institution performs a urine POCT hCG test in the ED prior to imaging, these may not be electronically submitted to the lab but found in clinical documentation in the ED.  You will need to audit the process in your institutions to make sure that these POCT tests are brought into the lab systems. 

So the most common hCG test in my institution for pregnancy is a quantitative test or testing for the presence above a threshold (PrThr). 

2106-3      Choriogonadotropin (pregnancy test)                       PrThr        Urine               CHEM    

Other tests which are frequently used to identify pregnancy (based on hCG) would be the following list:

19080-1    Choriogonadotropin                                                    ACnc        Ser/Plas          CHEM   

19180-9    Choriogonadotropin beta subunit.free                     ACnc        Ser/Plas          CHEM  

20415-6    Choriogonadotropin.beta subunit                              ACnc        Ser/Plas         CHEM 

20994-0    Choriogonadotropin                                                     Imp           Ser/Plas          CHEM   (Imp is Impression or Interpretation)

2107-1      Choriogonadotropin                                                     SCnc        Urine                CHEM   

2110-5      Choriogonadotropin.beta subunit (pregnancy)       PrThr        Ser/Plas          CHEM   

2111-3      Choriogonadotropin.beta subunit                              SCnc        Ser/Plas          CHEM

2112-1      Choriogonadotropin.beta subunit (pregnancy)       PrThr        Urine                CHEM  

2113-9      Choriogonadotropin.beta subunit in 24 hour           MRat        Urine                CHEM     (24 hr urine)

2114-7      Choriogonadotropin.beta subunit                              SCnc        Urine                CHEM 

2115-4      Choriogonadotropin beta subunit.free                      SCnc        Ser/Plas          CHEM    

2118-8      Choriogonadotropin (pregnancy test)                       PrThr       Ser/Plas           CHEM   

2119-6      Choriogonadotropin                                                     SCnc        Ser/Plas          CHEM   

21198-7    Choriogonadotropin.beta subunit                              ACnc        Ser/Plas         CHEM 

25372-4    Choriogonadotropin                                                     ACnc        Urine                CHEM   

25373-2    Choriogonadotropin beta subunit.free                      MCnc       Ser/Plas          CHEM  

34670-0    Choriogonadotropin                                                     MCnc       Ser/Plas          CHEM   

45194-8    Choriogonadotropin.intact+beta subunit                 ACnc        Ser/Plas          CHEM

55869-2    Choriogonadotropin.intact+beta subunit                 MCnc       Ser/Plas          CHEM

55870-0    Choriogonadotropin                                                     ACnc        BldCo              CHEM  

56497-1    Choriogonadotropin.beta subunit                              ARat         Urine               CHEM    (24 hr urine)

80384-1    Choriogonadotropin (pregnancy test)                       PrThr       Urine                CHEM   (bioMerieux bioNexia hCG Urine kit)

80385-8    Choriogonadotropin (pregnancy test)                       PrThr       Ser                   CHEM   (bioMerieux bioNexia hCG Combo kit)

83086-9    Choriogonadotropin                                                     ACnc        Ser/Plas          CHEM    (bioMerieux's VIDAS HCG assay)

93769-8    Choriogonadotropin.intact+beta subunit                 MCnc        Ser/Plas          CHEM 

Please see the definitions behind the following quality measures (HEDIS measures) for their pregnancy inclusion criteria:

https://www.bcbsil.com/provider/pdf/chlamydia_screening.pdf (CHL Measure)

https://loinc.org/96080-7/

We should align with standardized inclusion/exclusion definitions whenever possible. 

Thanks,

Gregory RN

[Melissa Armao]

Thank you Gregory!  Since I am compiling for several different facilities who may use different collections, I really appreciate your in depth responses!

[Gregory Briddick, Jr.]

You’re very welcome. I’ll work through the rest of the codes as time allows. Some of these should be based on value sets which are standardized (such as the INR group). CMS and other national quality groups have put together lists of SNOMED, LOINC, ICD-10CM/PCS, CPT, and other standardized ontological language codes to standardize exclusion/inclusion criteria and measures. As best as we can, we should align with these value sets. 

This is why the list I proposed for hCG includes uncommon in-hospital inpatient tests, but can indicate pregnancy. This list aligns with what is built out as an exclusion for the chlamydia HEDIS measure.   As soon as my UMLS license get renewed, I’ll post what CMS has created for their INR value set for their eCQM project. 

Thanks,

Gregory RN

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From: Melissa Armao <asideo...@gmail.com>
Sent: Thursday, June 10, 2021 8:50:49 AM
To: ny-sepsis-ehr-discuss <ny-sepsis-...@cloud.ipro.org>
Cc: gbri...@gmail.com <gbri...@gmail.com>; Melissa Armao <asideo...@gmail.com>
Subject: Re: LOINC Codes for Lab Tests

 

[Gregory Briddick, Jr.]

Alright, Let's look at influenza labs.....

When we think of influenza monitoring, we need to discriminate what we are looking to understand in the data.  We can focus on current infections (PCR/qPCR/RT-qPCR/viral cultures/antigen/immunofluorescence) vs. antibody presence (typically serum IGg/IGm).

If we are simply looking for a surveillance measure to understand how widespread influenza exposure was in the population, we would tend to use an antibody tests (typically hemagglutination inhibition or neutralization) for the specific protein in question (which would denote which type and subtype of influenza the antibody targets).  You wouldn't see antibody tests in the inpatient world, since they do not inform the clinician about whether the symptomology the patient is experiencing is due to influenza, as the antibody doesn't test for the presence of the virus itself.  Antibody testing is largely seen in the public health realm, so would be outside the scope of this collaborative.

In your influenza virus LOINC search, you defined the system as 'Ser', which denotes a serum test.  Defining the search to explicitly look for Serum labs will significantly reduce the reliability of the codes you are pulling.

In the inpatient world, our focus is on ruling in/out current infections, hence we need to focus our LOINC codes on tests which identify current infections, such as viral cultures, PCR, and antigen tests.  Often these tests are in a respiratory panel.  These panels often target multiple influenza subtypes or are part of a larger panel with many respiratory viruses (such as adenoviruses, enteroviruses, para-influenza, RSV, etc.) and sometimes bacterial sources (like diphtheria and pertussis). 

https://www.cdc.gov/flu/professionals/diagnosis/rtpcr-test-kits.htm

https://phinvads.cdc.gov/vads/ViewValueSet.action?id=2EFBC056-83A9-E311-8D07-0017A477041A#

There are a number of Value sets which denote the LOINC codes which should be used to identify Influenza screening during admission, segregated by the testing methodology.  Here is a list of the OIDs that define the population:

2.16.840.1.113762.1.4.1146.336      Influenza (Tests for influenza A or B virus Nucleic Acid)

https://vsac.nlm.nih.gov/valueset/2.16.840.1.113762.1.4.1146.336/expansion/Latest

2.16.840.1.113762.1.4.1146.337     Influenza (Tests for influenza A or B virus Antigen)

https://vsac.nlm.nih.gov/valueset/2.16.840.1.113762.1.4.1146.337/expansion/Latest

2.16.840.1.113762.1.4.1146.797      Influenza (Tests for influenza A or B virus by Culture and Identification Method)

https://vsac.nlm.nih.gov/valueset/2.16.840.1.113762.1.4.1146.797/expansion/Latest

Here is a list of some of the codes that we should be using:

   
LOINC_NUM            COMPONENT                                                                        PROPERTY                   SYSTEM     SCALE_TYP      METHOD_TYP                         CLASS         DefinitionDescription      
22825-4                    Influenza virus A Ag                                                             PrThr                             XXX              Ord                     Immune diffusion                   MICRO                                                       
22826-2                    Influenza virus A identified                                                 Prid                                XXX              Nom                   Bioassay                                  MICRO           Assesses the pathogenicity of virus strain by inoculation into young chickens and monitoring development of clinical signs and/or death.
22827-0                    Influenza virus A subtype                                                   Prid                                XXX               Nom                   Probe.amp.tar                        MICRO           Distinguishes between subtypes of low vs. high pathogenicity.
22828-8                   Influenza virus A subtype                                                    Prid                                XXX               Nom                   Immune diffusion                  MICRO           Distinguishes between subtypes of low vs. high pathogenicity.
23769-3                   Porcine influenza virus A Ag                                               PrThr                             Tiss               Ord                     Immune stain                         MICRO
23781-8                   Swine influenza virus Ag                                                      PrThr                            Tiss                Ord                      IF                                             MICRO
23782-6                   Swine influenza virus Ag                                                      PrThr                            Tiss                Ord                      Immune stain                       MICRO
24015-0                   Influenza virus A+B Ag                                                         PrThr                             XXX               Ord                                                                      MICRO
31858-4                   Influenza virus A Ag                                                              PrThr                            Thrt                 Ord                                                                     MICRO
31859-2                  Influenza virus A Ag                                                               PrThr                             XXX              Ord                                                                        MICRO
31860-0                   Influenza virus A+B Ag                                                         PrThr                             Thrt                Ord                                                                      MICRO
31863-4                   Influenza virus B Ag                                                              PrThr                              Thrt               Ord                                                                      MICRO
31864-2                   Influenza virus B Ag                                                              PrThr                              XXX              Ord                                                                      MICRO
33535-6                  Influenza virus A+B Ag                                                          PrThr                              Nph               Ord                                                                      MICRO
34487-9                   Influenza virus A RNA                                                           PrThr                              XXX              Ord                    Probe.amp.tar                         MICRO
38270-5                   Influenza virus A H7 RNA                                                     PrThr                              XXX              Ord                    Probe.amp.tar                        MICRO

38271-3                   Influenza virus A H6 RNA                                                     PrThr                              XXX             Ord                     Probe.amp.tar                        MICRO

I will attach an csv file with the remaining code, but I would recommend going to the source of these OIDs.

[Gregory Briddick, Jr.]

As far as INR.  In the list you provide, you have a large number of codes which capture many tests which aren't INR or related to the INR test.  With the INR, we should align with OID 2.16.840.1.113883.3.117.1.7.1.213 unless we want to include Fetal testing of INR (which seems like it would be an uncommon situation for Sepsis).

2.16.840.1.113883.3.117.1.7.1.213                                    INR

https://vsac.nlm.nih.gov/valueset/2.16.840.1.113883.3.117.1.7.1.213/expansion/Latest

34714-6                         Coagulation tissue factor induced.INR                                                          RelTime                  Bld                   Qn          Coag                  INR in Blood by Coagulation assay
38875-1                         Coagulation tissue factor induced.INR                                                          RelTime                  PPP/Bld          Qn          Coag                  INR in Platelet poor plasma or blood by Coagulation assay
46418-0                         Coagulation tissue factor induced.INR                                                          RelTime                  BldC                 Qn          Coag                  INR in Capillary blood by Coagulation assay
52129-4                         Coagulation tissue factor induced.INR^post heparin neutralization         RelTime                  PPP                 Qn          Coag                  INR in Platelet poor plasma by Coagulation assay --post heparin neutralization
6301-6                           Coagulation tissue factor induced.INR                                                          RelTime                  PPP                  Qn          Coag                  INR in Platelet poor plasma by Coagulation assay

These are the core INR LOINC codes (we don't need Goal INR or days to therapeutic range, etc.).  Monitoring the OID would allow the collaborative to stay abreast of new LOINC codes that may come into existence.

[Gregory Briddick, Jr.]

An update on the Lactate LOINC codes.  There are a few OIDs which cover the Lactate codes.  They mirror what I proposed above, for the most part.  I suggest that we align with one of them and be consistent.,

OID:  2.16.840.1.113762.1.4.1200.108       Blood Lactate level Sepsis Septic shock

https://vsac.nlm.nih.gov/valueset/2.16.840.1.113762.1.4.1200.108/expansion/Latest

OID:  3.4                  Blood Lactate level Sepsis Septic shock

https://vsac.nlm.nih.gov/valueset/3.4/expansion/Latest

OID:  2.16.840.1.113883.3.666.5.2096              Lactate  (SCnc only)

https://vsac.nlm.nih.gov/valueset/2.16.840.1.113883.3.666.5.2096/expansion/Latest

I would suggest either of the two initial OIDs, as they seem to be the most broad and cover both SCnc and MCnc labs.

On Wednesday, June 9, 2021 at 1:39:32 PM UTC-4 Gregory Briddick, Jr. wrote:

[Gregory Briddick, Jr.]

Bilirubin:

Bilirubin exists in multiple forms in the body, similarly to hCG, and we use a few different measurements to understand where in the process of creation, breakdown, and removal the body is having difficulties.  You will see three different ways that Bilirubin is commonly measured:  Total Bilirubin, Direct Bilirubin, Indirect Bilirubin.  Sometimes you will see direct bilirubin called conjugated and indirect as unconjugated.  This denotes the traditional lab process (Jendrassik Grof method) of how to find the conjugated through how much of the bilirubin is water soluble, and then subtracts this Direct (conjugated) from the total Bilirubin, giving us the estimated uncojugated bilirubin.  This becomes the indirect bilirubin, since the measurement isn't a direct measurement of the unconjugated, but rather an indirect measurement of the unconjugated levels.  Newer lab mechanisms can test for direct and indirect levels separately, but the name persists. 

https://labtestsonline.org/tests/bilirubin

Most organizations will report a Total Bili as part of their CMP, but there may be organizations which do not report a TBili routinely.  For these institutions, we can add the indirect and direct bilirubin levels and get an estimated TBili level.  Just like with Lactate, we have measurements for Bilirubin in MCnc and SCnc (mass vs moles).  The Data dictionary defines the TBili as a mass measurement (MCnc), so if your lab reports the TBili as an SCnc, you will need to convert the reading.  There are any number of resources online which can guide you in this conversion.

For the Data Dictionary, they are only asking for the Total Bilirubin, hence about 2/3 of the LOINC codes that you have on your list won't identify the appropriate values.

OIDs exists for Bilirubin testing. 

2.16.840.1.113883.3.666.5.2377     Bilirubin

https://vsac.nlm.nih.gov/valueset/2.16.840.1.113883.3.666.5.2377/expansion/Latest

There are six codes in the OID, two for SCnc and 4 for MCnc.  There are a few other codes which exist in LOINC, but these seem like they would be infrequently utilized.  I will add these codes to the 6 which are in the OID below.  I would first test the list from the OID and align with it, and only expand the list to the other codes if these do not result in the return of TBili levels.

SCnc:

14631-6                    Bilirubin                                           SCnc                   Ser/Plas           Qn                   CHEM           Bilirubin.total [Moles/volume] in Serum or Plasma

47994-9                    Bilirubin                                           SCnc                   BldCo                Qn                   CHEM           Bilirubin.total [Moles/volume] in Cord blood
54363-7                    Bilirubin                                           SCnc                   Bld                     Qn                   CHEM           Bilirubin.total [Moles/volume] in Blood

77137-8                    Bilirubin                                           SCnc                   Ser/Plas/Bld    Qn                   CHEM           Bilirubin.total [Moles/volume] in Serum, Plasma or Blood
89871-8                    Bilirubin                                           SCnc                   BldV                   Qn                  CHEM           Bilirubin.total [Moles/volume] in Venous blood
89872-6                    Bilirubin                                           SCnc                   BldA                  Qn                   CHEM            Bilirubin.total [Moles/volume] in Arterial blood

MCnc:

1975-2                      Bilirubin                                          MCnc                   Ser/Plas            Qn                  CHEM            Bilirubin.total [Mass/volume] in Serum or Plasma

42719-5                   Bilirubin                                          MCnc                    Bld                     Qn                  CHEM            Bilirubin.total [Mass/volume] in Blood 

48624-1                   Bilirubin                                          MCnc                    BldCo                Qn                  CHEM            Bilirubin.total [Mass/volume] in Cord blood 

59827-6                   Bilirubin                                          MCnc                    BldA                  Qn                  CHEM            Bilirubin.total [Mass/volume] in Arterial blood
59828-4                   Bilirubin                                          MCnc                    BldV                  Qn                  CHEM            Bilirubin.total [Mass/volume] in Venous blood

MSCnc:

35194-0                   Bilirubin                                          MSCnc                 Ser/Plas            Qn                  CHEM             Bilirubin.total [Mass or Moles/volume] in Serum or Plasma

I would recommend against the use of the MSCnc since it can return both MCnc and SCnc values and could add considerable complications to the code.

[Gregory Briddick, Jr.]

Creatinine:

Creatinine is a measurement of Creatinine levels in the blood (Serum or plasma). Creatinine is produced by the breakdown of phosphocreatinine during the process of energy creation in the muscle by creatine kinase (CK).  Production of Creatinine is dependent on Sex (males typically higher than female due to higher skeletal muscle mass), Age, diet (higher in high protein diets and low carb diets), Race, ACE-inhibitors, and a few other characteristics. 

Creatinine in Serum/plasma isn't exactly a definitive lab since a large number of factors can alter the Cr level, especially in a short term.  Creatinine is best measured over time, which would give a baseline Cr value. 

Excretion of Creatinine is done by the kidneys, almost exclusively.  Cr is excreted unchanged in urine.  In the clinical realm, we often use a variety of secondary labs to determine the extent of kidney dysfunction/function, to better understand the acute processes and where the kidneys are not correctly functioning.  This is where we have labs such as Glomerular Filtration Rate (GFR), Creatinine Clearance (CrCl), Fractional excretion of Sodium (FeNa), BUN/CR ratio, etc. 

Since the collaborative isn't looking for the secondary tests to rule out which kidney components are dysfunctional (at least not at this time) and is focusing on the presentation Cr level and max Cr level, we do not need to include GFR, CrCl, or any test which is a Challenge test.  Once we exclude GFR and CrCL, we are left with a select few LOINC codes.  It's also important to make sure that we are excluding Cr levels from sources outside of Bld, Ser/Plas, BldA, and BldV.  It is not uncommon to check Cr levels of bodily fluids to determine if the patient has a urinary leak,  or to check the urinary Cr level to make sure it is being excreted and to compare the Urinary Cr to the Plasma Cr to calculate the CrCl levels.

OID     1.3.6.1.4.1.6997.4.1.2.271.13.38343.1.1.999.665            Creatinine

Code               Description
14682-9          Creatinine                                                                                SCnc               Ser/Plas             Qn            CHEM                         Creatinine [Moles/volume] in Serum or Plasma

21232-4          Creatinine                                                                               SCnc                BldA                    Qn            CHEM                         Creatinine [Mass/volume] in Arterial blood

2160-0            Creatinine                                                                                MCnc              Ser/Plas             Qn            CHEM                         Creatinine [Mass/volume] in Serum or Plasma
35203-9          Creatinine                                                                               MSCnc            Ser/Plas             Qn             CHEM                        Creatinine [Mass or Moles/volume] in Serum or Plasma
38483-4          Creatinine                                                                               MCnc              Bld                       Qn             CHEM                        Creatinine [Mass/volume] in Blood
44784-7          Creatinine                                                                               MCnc              Ser/Plas             Qn             CHEM                        Creatinine [Mass/volume] (Maximum value during study) in Serum or Plasma
59826-8          Creatinine                                                                               SCnc               Bld                       Qn             CHEM                        Creatinine [Moles/volume] in Blood
77140-2          Creatinine                                                                               SCnc               Ser/Plas/Bld      Qn             CHEM                        Creatinine [Moles/volume] in Serum, Plasma or Blood

Creatinine post Vasopressin (Desmopressin) administration isn't a lab value that we are looking for in this collaborative.  Cr post AVP administration is a test we use to determine the causes of Diabetes Insipidus, and shouldn't be related to the current patient population that we are looking at (Sepsis).  https://www.ncbi.nlm.nih.gov/books/NBK537591/

https://emcrit.org/pulmcrit/vanish-renoresuscitation-vasopressin-vepinephrine/

You could look at adding the labs pre/post dialysis, but I don't think that these labs are likely present, based on my clinical experience.  My guess is that these labs are used in an outpatient basis or for estimating the effectiveness of dialysis.  This would be on an institutional basis, but my guess is that we shouldn't include them as they are unlikely to be representative in our population.

[Gregory Briddick, Jr.]

Platelets:

OK.  So platelets are part of a complete blood count, and indicates the measure of intact platelets within the blood.  These can be measured two different ways, predominately: Automated and Manual counts.  While large platelets and platelet mean volume are important measures for understanding the healthiness of the platelets, clumping is important in understanding platelet activation, and reticulated platelets in understanding the release of immature platelets.  All of these give us information and can help us interpreting the reported platelet counts, they are outside of the scope of the data dictionary and the required reported values. 

With what we are focusing on, we need to target the four different frequently reported platelet count labs,

OID:    2.16.840.1.113762.1.4.1222.146      Platelet Count

Code                      Description
26515-7                 Platelets                          NCnc              Bld               Qn                                           HEM/BC                     Platelets [#/volume] in Blood
49497-1                 Platelets                          NCnc              Bld               Qn              Estimate             HEM/BC                     Platelets [#/volume] in Blood by Estimate
777-3                      Platelets                          NCnc             Bld                Qn        Automated count   HEM/BC                     Platelets [#/volume] in Blood by Automated count
778-1                      Platelets                         NCnc              Bld                Qn         Manual count        HEM/BC                     Platelets [#/volume] in Blood by Manual count

Your labs may be part of a Platelet Panel, so you may need to check this also:

53800-9                Platelets panel                                        Bld               Qn          Automated count      PANEL.HEM/BC     Platelets panel - Blood by Automated count