Friday, August 08, 2025
ProJR Biochemistry: Patient outcomes of different HbA1c methodologies in low resource rural settings
SUMMARY:
This study compares patient outcomes of different HbA1c methodologies in low-resource rural settings. HbA1c is a crucial test for managing diabetes, but access to laboratory-based testing can be limited in rural areas. The study evaluates the effectiveness of various point-of-care (POC) HbA1c testing methods, including their accuracy, precision, and impact on patient care.
Keywords
- HbA1c
- Point-of-care testing
- Low-resource settings
- Rural healthcare
- Diabetes management
- Patient outcomes
- POC testing
- Glycemic control
Possible Research Questions
- What are the differences in patient outcomes between POC HbA1c testing and laboratory-based testing in rural settings?
- How do different POC HbA1c methodologies compare in terms of accuracy and precision?
- What is the impact of POC HbA1c testing on diabetes management and patient care in low-resource rural settings?
Potential Study Design
- Comparative study of different HbA1c methodologies (POC vs. laboratory-based)
- Evaluation of patient outcomes (e.g., glycemic control, treatment adjustments)
- Assessment of accuracy and precision of POC HbA1c testing methods
Implications
The study's findings could inform the development of effective and accessible HbA1c testing strategies for rural areas, ultimately improving diabetes management and patient outcomes in low-resource settings.
Conversational Transcripts extracted from the link below:
18-07-2025 20:41] PPM 1: @24F PA can you try looking up the evidence of efficacy of the enzymatic method of evaluating Hba1c as done in this patient's report above over the standard method with some web 2.0 help from @PPM3 @PPM4 and Web 3.0 help from @PPM5
[18-07-2025 20:42] PPM 4: Yes sir, I’ll share my findings here
[18-07-2025 20:42] PPM 1: @24F PA ask what symptoms made her suspect urinary infection and get tested with a urine culture?
[18-07-2025 20:42] PA: Infection ar jonoo ai madicine ta khache
[18-07-2025 21:03] PPM 4: P: 96 individuals, 70 diabetic and 26 non-diabetics
I: Measuring enzymatic HbA1c off-site as compared to HPLC on-site
C: HPLC and enzymatic HbA1C values of the same sample, HPLC done on-site on the same day and enzymatic HbA1C done one day later off-site, with proper collection and sample storage and transport protocols followed.
O: EA-HbA1c levels were approximately 0.3% lower than estimated HPLC-HbA1c with significance. These results of falsely low HbA1c levels underestimate diabetes mellitus.
The same article mentions that enzymatic assay can be used for screening purposes as it is low cost and processes samples quicker, justifying its use over the gold standard, HPLC.
19-07-2025 21:00] PPM 5: ### Comprehensive Analysis of HbA1c Estimation Methods and Comparison with Latex Agglutination Inhibition
#### *1. Globally Popular HbA1c Estimation Methods*
1. *High-Performance Liquid Chromatography (HPLC)*
- *Principle*: Separates HbA1c from other hemoglobin variants using cation-exchange columns.
- *Usage*: Gold standard in 70% of high-resource labs; NGSP/IFCC-certified for diagnostic use.
- *Pros*: High precision (CV <1%), detects hemoglobinopathies.
- *Cons*: Expensive equipment, requires skilled technicians, slow throughput (15–30 mins/sample).
2. *Enzymatic Assays*
- *Principle*: Uses enzymes (e.g., fructosyl peptide oxidase) to cleave glycated valine, producing measurable color.
- *Usage*: Growing adoption due to automation on clinical chemistry analyzers.
- *Pros*: Resistant to hemoglobin variants, cost-effective for high-volume labs.
- *Cons*: Moderate precision (CV 1.5–2%); may overestimate in severe anemia.
3. *Immunoassays (Turbidimetric/Chemiluminescent) *
- *Principle*: Antibodies bind specifically to β-N-terminal glycated hemoglobin.
- *Usage*: Dominant in hospital labs (e.g., Roche Cobas, Abbott Architect).
- *Pros*: Fast (<10 mins), integrates with routine analyzers.
- *Cons*: Vulnerable to interferences (e.g., carbamylated hemoglobin in CKD).
4. *Capillary Electrophoresis*
- *Principle*: Separates hemoglobin variants by charge/mobility in silica capillaries.
- *Usage*: Emerging in specialized labs; excels in variant detection.
- *Pros*: High resolution, minimal sample volume.
- *Cons*: Cost-prohibitive, limited scalability.
5. *Boronate Affinity Chromatography*
Principle*: Binds cis-diol groups of glycated hemoglobin to boronate matrices.
- *Usage*: Common where hemoglobin variants are prevalent.
- *Pros*: Measures total glycated hemoglobin (not just HbA1c); robust interference resistance.
- *Cons*: Overestimates HbA1c by 1–2% due to non-specific binding.
#### *2. Latex Agglutination Inhibition (LAI) Method*
- *Principle*: Latex particles coated with HbA1c antibodies agglutinate inversely to HbA1c concentration.
- *Typical Use*: Point-of-care or resource-limited settings due to simplicity.
#### *3. LAI vs. Other Methods: Analytical Comparison*
Table: Key Comparison Metrics
| *Parameter* | *LAI* | *HPLC* | *Enzymatic* | *Immunoassays* |
|---------------------|-------
| *Precision (CV%)* | 3–5% | 0.8–1.5% | 1.5–2% | 1–2% |
| *Time/Sample* | 10–15 mins | 15–30 mins | 10 mins | <10 mins |
| *Cost/Test* | $2–4 | $8–12 | $5–8 | $6–10 |
| *Interference* | High (lipemia, anemia) | Low (except Hb variants) | Moderate (anemia) | High (CKD, variants) |
| *Correlation to HPLC* | r=0.76–0.85 | Reference | r=0.98 | r=0.95 |
#### *4. Limitations of LAI in Clinical Practice*
- *Accuracy Issues*: Bland-Altman analyses show mean bias of +0.6% vs. HPLC, risking under-treatment if HbA1c is 7–8%.
- *Interference Vulnerabilities*:
- Falsely low values in inflammation (ESR >40 mm/hr) or hemolysis.
- Lipemia (triglycerides >500 mg/dL) causes false highs.
- *Standardization Gaps*: Not traceable to IFCC reference methods; calibration drifts common.
#### *5. When LAI May Be Appropriate*
- *Resource-Limited Settings*: Costs 50% less than HPLC; minimal training needed.
- *Screening Use*: Suitable for stable T2DM without comorbidities (anemia, CKD, hemoglobinopathies).
- *Rapid Triage*: ER/outpatient settings needing same-day results.
#### *6. Recommendations for Institutions Using LAI*
1. *Validation Protocol*:
- Run parallel tests with HPLC/enzymatic methods quarterly.
- Exclude samples from patients with anemia (Hb <11 g/dL) or active inflammation.
2. *Clinical Correlation*:
- Confirm LAI >7.5% with lab-based methods before therapy escalation.
3. *Transition Strategies*:
- Adopt enzymatic assays for central labs (optimal cost/accuracy balance).
- Reserve LAI for remote clinics with rigorous QC.
# *Conclusion*
While latex agglutination inhibition offers speed and affordability, its analytical limitations necessitate cautious use in complex patients. HPLC and enzymatic methods remain superior for diagnostic and management decisions. Institutions using LAI should implement strict validation protocols and prioritize method migration for high-risk cohorts. Global standardization efforts (IFCC/NGSP) continue to emphasize accuracy over convenience.
[19-07-2025 21:06] PPM 1: Thanks. This was very useful for our institution
[13-08-2025 13.23] PPM 1: Okay found out that "from January to August 2018 in Nizams, HbA1c quantification was carried out on a Variant II Bio-Rad’s HPLC analyzer." Unquote https://ajmb.umsha.ac.ir/FullHtml/ajmb-2250
So perhaps we can attach this as a reference in the ProJR patient related outcome data for the above patient
[07-10-2025 16.26] cm: Afternoon session:
45M diagnosed diabetes on June 2025
Lean phenotype without trunkal obesity
Was initially evaluated in ESI hospital Choutuppal and started on glimiperide, metformin, sitagliptin and later even mixtard insulin was added.
Currently admitted due to altered sensorium and some vague history of hypoglycemia two days back with MRI showing csvd in the pons.
His son 24M was diagnosed diabetes and is on insulin mixtard twice a day since October 2024!
@pajr.in CEO, NHS Endocrinologist this is also one of the patients who's Hba1c has been documented to break the Narketpally turbilatex ceiling of 8 with a value of 9! There's another one @PGKims 2023 knows had 10 and there's another one with 13 admitted today! Suddenly a breakthrough cluster in our Narketpally Hba1c!
[07-10-2025 16.26] cm: More details about the above paient available in the below link. 👇https://pajrcasereporter.blogspot.com/2025/10/55m-altered-sensorium-3-days-t2dm-3.html
[07-10-2025 16.30] cm: Afternoon session:
Here's the other 45M with denovo diabetes, Hba1c of 13 and DKA!
He's also quite lean without trunkal obesity and I hope to share his details tomorrow
[07-10-2025 16.30] cm: For more details about this patientavailable in the below link 👇
[11-10-2025 12.36] cm: More details about this 55F diabetes patient available in the below links.👇
[09/10, 13:06] : @Dr thanks for drawing our attention to the issue of our Hba1c two years back when you during the course of collecting your thesis data pointed out that none of our Hba1c reports were exceeding 8-9 and we had been closely following up our Hba1c values in all our diabetes patients since then and were convinced about what you pointed out, also found out that it could potentially be related to our methodology that doesn't use HPLC but uses latex immunoturbidimetry and we also discussed this issue with the biochemistry faculty in various monthly admin meetings during 2023 itself. Had requested for audit of our Hba1c registers to document this suspected phenomenon of mean lower Hba1c levels in our diabetic population largely due to methodology issues but it didn't happen due to logistics.
Finally last week we have suddenly noticed a few patients who have started showing higher values from 10-13 with perfect expected clinical correlation, something that we had stopped expecting from our Hba1c s till now!
Just thought I would share this institutional Hba1c turnaround milestone with everyone also in the hope of learning as to how and why this turnaround happened or was it all a misinterpretation on our part all along.
Shared in the group to maximize learning inputs at risk of causing communal disharmony.
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