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Diabetic Cat Care

Tight Regulation Case Study

 Macchia, a Feline with Acromegaly

Macchia, Acro Angel, GA 2016

The purpose of this case study presentation is to highlight how well Tight Regulation (TR) can and does work for cats with Acromegaly and to encourage owners of cats with high insulin needs, whether from Acromegaly, Cushing's, IAA or “just because”, to consider TR as an option to significantly help keep your cat as well-regulated as possible. 

History

Macchia was diagnosed FD in August of 2013; treated with Caninsulin dosed every 12 hours. Prescribed doses were increased to 6.0u over the course of a month with no success in regulating BG. Macchia’s insulin was switched September 2013 to the longer lasting depot insulin Lantus. In the spring of 2014 after discovering Dr. Lisa Pierson’s feline nutrition site, Macchia was switched to a lower carb wet diet of approximately 10% dry matter carbs (at the top end of what is recommended for TR). A slight heart murmur was mentioned during a vet visit in 2014 which the vet commented was “normal for a cat over 10 years of age”. Lantus doses were repeatedly increased with little to no effect. At the time the owner, Silva, and Macchia arrived at DCC, the prescribed dose of Lantus was 12.0u BID, 24.0u total daily. Home testing of BG was taking place; Silva was very familiar with Macchia’s curves. Macchia has had no clinical hypos from the time of diagnosis to present, regardless of insulin dose.

Arrival at DCC

The very day Silva first posted Macchia's test log at DCC, the prospect of Acromegaly being a reason behind Macchia’s high insulin needs was mentioned. Silva was encouraged to read the documentation DCC provides so she could decide about starting TR, and to allow for time to determine what if any changes would need to take place. Monitoring Macchia’s response to the insulin, along with slight changes that could be made prior to starting TR (for example, earlier timing of insulin shots, and change to an even lower carb wet food) might provide some answers behind her high insulin needs. In addition, taking the time to watch results unfold would help in determining which form of the Detox Process would be best suited to Macchia’s case.

Silva has been very proactive and intuitive when it’s come to Macchia’s care. December 21, with BG very high, Macchia was given a shot of Lantus at +8 which produced positive results which worked to increase the overlap between doses and dropped the BG nicely although not down below 8.3/150. Due to Macchia’s high insulin needs and very high BG, an individualized approach to the Detox Process was recommended; partially in consideration of the fact Macchia was already on a fairly low carb diet. The Detox Process would take place with continued insulin at the current dose through the 24 hour detox period while closely monitoring BG. December 23, the 2-5% DM carb food arrived and Macchia’s diet was changed; again Macchia had a very positive response to the minor changes; both to the lower carb food and earlier shots given at +11 however she did not drop down to normal range BG. December 24, 24 hours after the switch to lower carb food Macchia’s insulin dose was reduced by 1.0u, coupled with another earlier shot at +11 and normal range BG was the result! A great start!

December 28 it was confirmed the syringes being used were U100 insulin syringes without half unit marks. The recommendation was made to purchase 3/10cc syringes with half unit marks to allow for more accurate incremental dosing in amounts of 0.25u, 0.5u and 0.75u. While waiting for the new syringes to arrive, Silva began to question the syringes she had been using since the time Lantus had been prescribed. On January 2, it was confirmed every line on the syringe represented 2.0u of insulin instead of 1.0u as she’d been told by the vet. Macchia had been receiving double the amount of insulin believed since starting Lantus – not 24.0u but 48.0u daily!!!!!!

This discovery brought another possibility to the table - perhaps the problem with regulating Macchia might not be Acromegaly; rather, was it possible the apparent need for such high doses could actually be the result of severe Chronic Rebound from the time Lantus was prescribed?

Silva was able to purchase the correct syringes January 3 and also was able to obtain fast-acting insulin (Novo-Rapid) which was recommended as a “tool” to have in the event it was needed.

In light of the dosing error, the new goal became confirming or denying whether or not Macchia actually needed the large doses of insulin she’d been getting by mistake. Since the measurement error had been made right from the time of the switch to Lantus, rather than take more time extending out the insulin reduction process, the plan was to give +24 hours between doses of Lantus to allow for an excessive depot from potentially consistent over-dosing to dissipate as much as possible. Fortunately the timing worked out that Macchia was coming off a fantastic run in great numbers; the likelihood of ketones being produced had been significantly reduced.

Macchia’s TR Journey Begins

In Macchia’s case, it was determined rather than begin at the conservative sliding scale typically recommended at the start of TR (first rung dose of 0.25u) after the 24 hour withhold of insulin to dissipate potential Chronic Rebound, Macchia’s individualized dosing scale would be set higher.

BG US ( mg/dl) Metric (mmol/L) Dose
150 - 250..........8.3 - 13.9...........2.00u
251 - 400.........14.0 - 22.0...........2.25u
400+...............22.2+.................2.50u

Macchia’s start to TR was slightly different than the norm because of the above mentioned dosing error. The strategy was to start with very close monitoring and two +12 shots after withholding insulin for +24 hours, allowing for the Lantus depot to lessen further over the initial 48 hour period. Depending on BG testing during this time, if needed, the timing of shots might very quickly change to +10 dosing. In addition, if Macchia’s BG spiked high, Novorapid (NR) would be added into the mix to quickly reduce BG. NR would only be used during a very small window (between +6 and +8, after nadir but before the BG started to rise too much). The aim of the timing for NR was to allow for the NR to be out of the system for the most part by +12, so as to not interfere when it came to the goal of achieving a successful +12 dosing scale with Lantus. It was time to learn what Macchia had to “say”.

During the time from January 5 to January 13, 2015, Macchia’s Lantus scale was increased starting with 0.5 increments, then with 1.0u and 2.0u increments depending on Macchia’s results. Increases were given every two to three shots if needed. It was quickly becoming increasingly clear that Macchia was in fact requiring high doses of insulin (albeit not as high as during the time of the dosing error), and once again discussion about making the switch from Lantus to Levemir occurred.  In addition, the recommendation to test for Acromegaly would confirm or deny if that was what Silva was dealing with.

The reason for the recommended switch to Levemir was based on the fact it is proving to be very suitable insulin for cats, and particularly those with high insulin needs. The reason is believed to be due to Levemir’s unique method of absorption, it’s longer, gentler curve, and that it has a neutral PH (where the PH of Lantus is 4, a cat’s normal PH is approximately 6.5).

On January 19, 2015; Silva had Macchia tested for Acromegaly and as well Cushing's where dexamethasone was administered to identify cortisol levels. In addition it was discovered that Macchia had a gum infection and antibiotics were prescribed. On top of this, a steady diet of +10 dosing and the stress of knowing something was seriously wrong with Macchia resulted in the need to switch to a +12 dosing schedule. Needless to say all things in the mix; Macchia’s BG was less easily controlled and on February 1, and February 7, shots of fast-acting insulin were used to bring her BG back down quickly.

On February 2, the results of insulin resistance testing were back. Macchia was negative for Cushing's, but it was confirmed – Macchia was Acromegalic. Her results were 1600 where the value limit is 1000. It was devastating news.

By February 8th, Macchia’s first rung dose of Lantus had increased to 18.75u, yet she was still not very well regulated and was now having breathing issues. Even though current doses at this time were approximately 5.0u less than had been given for months and with shorter dosing times in the mix, still there were only sporadic normal range results being achieved. At the vet visit to deal with breathing issues, it was decided that insulin would immediately be switched to Levemir.

On February 9, Macchia received her first shot of Levemir which was reduced by only 0.75 from her current Lantus scale. There was no allowing for an extended period of time between the last dose of Lantus and the first dose of Levemir which is the standard when switching insulin types; it was clear that Macchia needed a lot of insulin and the likelihood was that while the two insulin types could possibly produce a lower than desired result on the first or second shot as the Lantus worked its way out of Macchia’s system and the Levemir was introduced – as is the way with TR’s safety net of a low carb wet diet; with Silva’s very dedicated and frequent monitoring the lows would be far better than the highs she had been experiencing.

The very pleasant outcome from making the switch to Levemir? Macchia’s BG immediately dropped below renal threshold for two entire days in a row, the first time this had occurred! In addition, Silva shared with her fellow members that Macchia seemed much more alive, her eyes were bright, and she was not as depressed as she’d seemed on Lantus. This was very encouraging news after only two days!

On February 20, Silva had the IGF-1 redone with the result being Macchia’s result had dropped from 1600 to 1353, reconfirming the Acromegaly diagnosis. Silva’s strong instincts when it comes to Macchia’s needs lead her to continue dosing reductions from the 19.0u she’d received at the start of Lev, finally landing at a scale dose of 12.0u BID in March. In fact, Silva’s ability to keep Macchia very tightly regulated consistently was to the point that Macchia was predictable enough in her response, it was just as if Macchia was receiving static doses. Silva is to be highly commended for her efforts to get and keep Macchia very tightly regulated and in such consistently good numbers.

From March through to August, Macchia’s insulin scale did not vary by more than 4.0u over the 5 month period, with adjustments to doses being gradual and made methodically over time. Such a variance over a 5 month period is not out of the realm when it comes to dealing with “simple” diabetic cats; but when dealing with the disease of Acromegaly and the unpredictable not to mention unknown variances in degree of hormonal output from the tumor, clearly Macchia’s results to Tight Regulation’s approach speaks volumes when it comes to TR being a very successful method to regulate cats with Acromegaly – SAFELY. Macchia has not experienced any sudden drops, nor has her BG ever been “too low” at any time. Her results have been nothing but steady, and more importantly – very predictable – as a direct result of understanding the effects of overlap, depot, the action of how different insulin types work, using them appropriately; and most important how the individual cat processes their insulin.

As is clear looking at Macchia’s test logs (links below), she is truly a poster child when it comes to successful Tight Regulation, Acromegalic or not. The sliding scale approach of working to identify insulin needs in a methodical way; then giving the right amount of insulin for the BG at the right time based on identified patterns – works extremely well.

The next 6 months;  2015

In mid-July Silva determined that it was time to start Macchia on Gabapentin to help reduce any pain. On August 19, 2015, Macchia started Pasireotide treatment which, as communicated by the RVC, would very quickly have an effect on Macchia’s insulin sensitivity allowing for a significant reduction to insulin doses within a matter of days. This proved to be entirely true; Macchia’s scale dropped from 12.0u BID with +12 dosing on Day One of Pasireotide, to 1.75u BID by Day Four. Prior to starting Pasireotide, baseline blood work was done, as well as ultrasound on the abdomen and heart with positive results. The one known and very unfortunate side effect of Pasireotide treatment has been chronic diarrhea. Probiotics, digestive enzymes and Bentonite clay based medication were added to Macchia’s support remedy regime to try to alleviate this side effect and worked well.

Macchia’s full  test log detailing her complete TR journey, links to specific month's BG test data, approach to insulin dosing and the introduction of Pasireotide treatment on August 19, 2015 is located here.

Summary

Unfortunately, the leading treatments for Acromegaly are expensive and are not available globally as yet. Surgery and radiotherapy offer the most chance to cure Acromegaly; but the chance of life time hormone replacement medications being necessary is a possibility. As is the case with any tumor, there is the chance the tumor might return. To date, there is not enough quantitative data to prove permanent cure but the studies continue and as a result of the devoted efforts by veterinary specialists around the world to understand diseases such as diabetes and Acromegaly in cats; firm findings will hopefully be confirmed or denied very soon. Drugs such as Pasireotide are available to significantly reduce insulin needs and perhaps reduce the size of the pituitary tumor, but they too are not a cure and come with their own side effects as well as significant expense. The consistent result of all leading edge treatment therapies at this time has proved to significantly reduce, or eliminate for some cats, the need for exogenous insulin.

Conclusion

Whether or not you are able to pursue the new but costly treatment options available, tightly regulating the diabetes caused by Acromegaly’s effect on insulin sensitivity is the best thing you can do for your cat to avoid permanent and irreversible damage to internal organs. Just as is the case with “simple” FD, TR has navigated many cats into diet controlled diabetic remission and this has proven to be true for Acro cats too.  If not remission, becoming very well-regulated is achievable as has been the case for Macchia, even prior to starting Pasireotide treatment.

DCC’s goal in presenting this case study is to provide a successful model for responsible use of insulin when it comes to cats needing high doses, whether that is a result of Acromegaly, Cushing's, IAA, or “just because they do”.

Macchia’s case study is a compelling example that Dr. Elizabeth Hodgkin’s Tight Regulation Protocol works very well for high dose cats. Macchia’s experience with TR is a testament that a knowledgeable and methodical approach as well as responsible use when it comes to both basal and bolus insulin types , even with potential hormonal fluctuations, is very safe and can be highly successful.

Should your cat be needing high doses of insulin without much success when it comes to regulating BG, and/or you have any questions about DCC’s approach to Tight Regulation, please post on the Talking TR forum.

Update January 2016

Pasirotide is a very expensive drug - costing approximately 3.500 Euros/$4500 USD for a 4 month supply - many efforts were made to try to source more for Macchia.  Unfortunately as the Pasireotide was being weaned, various aggressive signs of the disease started to present.  Macchia lost her battle with Acromegaly within a few weeks after the Pasirotide was finished.  Macchia will always stand as an undeniable testimonial when it comes to how well TR works for Acro cats and her journey is a clear example as to how significantly and quickly Pasirotide works to lower insulin needs in cats with Acromegaly.  Silva and DCC will always be grateful to Dr. Ruth at the RVC for the guidance provided for Macchia on her Acro journey.

Rest in peace beautiful Macchia, may you always be an inspiration of hope to other owners with cats whose diabetes has presented as a result of Acromegaly, or have high insulin needs for whatever reason.