Month 22, Part B

Thursday, 5/18 – I fell asleep mid morning and woke up at about 12:30 with a growing feeling of nausea. The nausea got worse through the afternoon, and when my wife got home for school at about 3:15 (and was planning to leave in a very short while for a three day conference she had been helping plan for), I really felt like vomiting, but I resisted because I didn’t want her to feel like she should stay home with me and not go to her conference. When she left, I felt so bad that I tried to vomit, but I failed. However, I did start in with some diarrhea. I soon fell asleep again and slept for about an hour, after which, the nausea had subsided quite a bit, although I had no appetite at all. The diarrhea continued for the next 2 days.

Sunday, 5/21 – No diarrhea with a small amount of solid stools. My appetite started to return, although all food continues to be repulsive to some degree because everything tastes terrible to me. My taste has been off since my transplant, but this is much worse than it’s ever been before.

My pulmonary doctor called in the evening (from a pulmonary conference in San Diego as it turns out) and said he had been thinking about my case and decided that Dapsone might be the cause of my low pulse ox readings because it can turn the skin blue. He said I should stop taking the Dapsone, and since I really dislike taking any meds, I readily complied.
I had been taking Dapsone since the transplant, and was never sure what it was for. The pharmaceutical sheet that comes with the prescription says “Dapsone is used to treat leprosy and other skin diseases.” When I later asked my other doctors what it was for, they said it is to prevent a type of pneumonia they refer to as PCP (pnuemocystis carinii pneumonia), which is an opportunistic disease that is one of the more common causes of death for HIV/AIDS patients. They are quite wary of it in all immune suppressed patients. I did some research on my own and found out that Dapsone can very rarely cause methemoglobinemia.

WARNING – this paragraph contains a simplified, but somewhat techinal explanation of methemoglinemia which I got at http://www.emedicine.com/EMERG/topic313.htm. You may or may not be interested. Normally, hemoglobin (red blood cells) contain iron molecules in a state that they can combine with oxygen by sharing an electron, becoming oxyhemoglobin. When oxyhemoglobin releases the oxygen to tissues, it can again comgine with oxygen. Sometimes the hemoglobin becomes oxidized, the iron becomes incapable of transporting oxygen, and it is then called methemoglobin.

History:

• Normal methemoglobin concentrations are 1% (range, 0-3%).
• At concentrations of 3-15%, a slight discoloration (eg, pale, gray, blue) of the skin may be present.
• At fractions of 15-20%, the patient may be relatively asymptomatic, but cyanosis is likely to be present.
• Signs and symptoms at fractions of 25-50% are as follows:
  Headache
  Dyspnea
  Lightheadedness
  Weakness
  Confusion
  Palpitations, chest pain
• Signs and symptoms at fractions of 50-70% are as follows:
  Altered mental status
  Delirium

Physical:

• Discoloration of the skin and blood is the most striking physical finding.
• Cyanosis occurs with the formation of 1.5 g/dL of methemoglobin, as compared to 5 g/dL of deoxygenated hemoglobin.
• Seizures
• Coma
• Dysrhythmias (eg, bradyarrhythmia, ventricular dysrhythmia)
• Acidosis
• Cardiac or neurologic ischemia

END WARNING.

So Dapsone can cause methemoglobinemia, which can cause some of the symptoms I had been manifesting, such as cyanosis (blue lips and skin), weakness, anemia, etc. It apparently can also have more serious conseqences, such as coma and death. I didn’t get my methemoglobin levels tested until after I had been off Dapsone for more than a week and was feeling much better, at which time it was normal.

Monday, 5/22 through Saturday, 5/27 – I had diarrhea throughout this period and still got winded very easily. I finally went back to work on Thursday and Friday.

Saturday, 5/27 – no diarrhea since about noon and energy started to return. My taste also started to return to pre-intestinal virus levels.

Sunday, 5/28 – rode my bike to church and back, and hit tennis balls for a little less than an hour.

Tuesday, 5/30 – regularly scheduled BMT clinic visit. My counts were good:

...... current normal

..... ------- ---------
WBC.. 5.6 ..... 4 – 11
Hgb.. 10.0 ... 14 – 18
Plt.. 284 ... 150 – 400

Most surprisingly, my pulse ox readings (via finger sensor) were 97 – 98! I would have been happy if it had returned to 91, where it was in the winter before it started plummeting. I don’t ever remember levels that high. The doctor and PA were both very happy with counts, and were smiling because they said I looked so much better. I had some color other than white or blue I guess. Even when I was cyanotic, I couldn’t see the difference, but my doctor said that I’ve been on Dapsone since long before she started seeing me, so she never knew what my normal coloring was before.

They cut one of my immune suppressants (Cellcept) in half – from 2 to 1 (and down from 4 a while ago), and my Prednisone from 7.5 to 5. The doctor also explained that anemia can be caused by a virus (there were other corroborating indicators), and that diarrhea can be caused by an antibiotic and sometimes there is even a delay.

As we were talking about my history, the doctor mentioned that because they have lowered the generally accepted criterion for AML (acute myelogenous leukemia), which is what I was headed for, if I came in now with the same level of blasts in my bloodstream as I had a year and a half ago, I would probably be given chemotherapy treatments to get them down to a lower level before doing a transplant. She says I was lucky that the graft versus leukemia effect was strong enough in my case to kill off the diseased bone marrow.

To catch up to today (6/10), I’m still feeling quite good, with my appetite returned and a good level of energy.

Love,
Justin