We ended the year with 28% organic sales growth in the fourth quarter.
Our proprietary products segment led the way with 37% organic sales growth, and all of this was fueled by high-value products, resulting in impressive gross and operating margin expansion for the quarter.
We shipped over 45 billion components touching billions of patient lives.
And we donated over $2.5 million, but more importantly, over 3,600 hours, volunteer hours were donated by team members to help our local communities with the greatest needs.
We are introducing full year 2022 financial guidance that assumes approximately 10% organic sales, led by strong HVP sales and another strong year of both gross and operating profit margin expansion well in excess of 100 basis points.
For the past few years, we have set our long-term financial construct as annual organic sales growth of 6% to 8%, led by HVP sales and annual operating profit margin expansion of 100 basis points per year.
Over the past five years, we've had an annual organic sales CAGR of 13% and annual operating profit margin expansion of 240 basis points per year.
We are updating our long-term construct to annual sales growth of 7% to 9%.
And we continue to expect to expand operating margins by 100 basis points per year over the next few years.
Our financial results are summarized on Slide 10 and the reconciliation of non-U.S. GAAP measures are described in Slides 19 to 22.
We recorded net sales of $730.8 million in the quarter, representing organic sales growth of 28.3%.
COVID-related net revenues are estimated to have been approximately $124 million in the quarter.
proprietary products sales grew organically by 36.8% in the quarter.
High-value products, which made up approximately 74% of proprietary product sales in the quarter grew double digits and had solid momentum across all of our market units in Q4.
And contract manufacturing organic net sales declined by 2.1% in the fourth quarter primarily driven by lower sales of healthcare-related medical devices.
We recorded $300.6 million in gross profit, $89.5 million or 42.4% above Q4 of last year.
And our gross profit margin of 41.1% was a 470-basis-point expansion from the same period last year.
We saw improvement in adjusted operating profit with $189.2 million recorded this quarter compared to $119.1 million in the same period last year for a 58.9% increase.
Our adjusted operating profit margin of 25.9% was a 540-basis-point increase from the same period last year.
Finally, adjusted diluted earnings per share grew 52% for Q4.
Excluding stock-based compensation tax benefit of $0.06 in Q4, earnings per share grew by approximately 58%.
Volume and mix contributed $153 million or 26.4 percentage points of growth, including approximately $78 million of incremental volume driven by COVID-19-related net demand.
Sales price increases contributed $11.3 million or 1.9 percentage points of growth.
Slide 13 shows our consolidated gross profit margin of 41.1% for Q4 2021, up from 36.4% in Q4 2020.
proprietary products fourth quarter gross profit margin of 46.3% was 460 basis points above the margin achieved in the fourth quarter of 2020.
Contract manufacturing fourth quarter gross profit margin of 16.5% was 70 basis points below the margin achieved in the fourth quarter of 2020.
Operating cash flow was $584 million for the year, an increase of $111.5 million compared to the same period last year, a 23.6% increase.
In 2021, we spent over $253 million on capital expenditures, a 45% increase over 2020.
We expanded capacity at 13 existing sites with 13 major facility modifications and over 400 pieces of equipment, all while keeping pace with the growing demand.
Working capital of approximately $1.1 billion increased by $277.6 million from 2020 primarily due to higher accounts receivable from our increased sales, higher inventory levels and an increase in our cash position.
Our cash balance at December 31 of $762.6 million was $147.1 million higher in our December 2020 balance.
Full year 2022 sales guidance will be in a range of $3.05 billion to $3.075 billion.
There is an estimated headwind of $70 million based on current foreign exchange rates.
We expect organic sales growth to be approximately 10%.
We expect our full year 2022 reported diluted earnings per share guidance to be in a range of $9.20 to $9.35.
Also, our capex guidance is $380 million for the year.
Estimated FX headwind on earnings per share has an impact of approximately $0.21 based on current foreign currency exchange rates.

Summary:
We recorded net sales of $730.8 million in the quarter, representing organic sales growth of 28.3%.
Contract manufacturing fourth quarter gross profit margin of 16.5% was 70 basis points below the margin achieved in the fourth quarter of 2020.
Full year 2022 sales guidance will be in a range of $3.05 billion to $3.075 billion.
There is an estimated headwind of $70 million based on current foreign exchange rates.
We expect our full year 2022 reported diluted earnings per share guidance to be in a range of $9.20 to $9.35.