Can the PCR blood test identify hypnozoites?

QUESTION

I have never been diagnosed with malaria but returned from Turkey in 2007 (P. Vivax endemic area; Diarbykar & Mardin areas). My symptoms were consistent with malaria and I have now had 5 relapses since then, averaging one occurrence per year. I now have impaired kidney functioning and I am uncertain if this could be because of undiagnosed malaria? Would the PCR blood test at anytime be an option to conclusively rule out malaria or would blood need to be drawn during an actual relapsing event?

ANSWER

You have certainly done your research! It’s great to hear from someone who is so well informed about the risk areas they traveled too and the diagnostic options. You’re right in thinking that PCR is only appropriate during an active relapse; while the malaria parasites are dormant in the liver (called hypnozoites, in that form), they are extremely hard to detect. One option could be to investigate the possibility of taking a test to look for antibodies to the P. vivax parasite. These tests are often referred to as ELISAs (enzyme-linked immunosorbent assays) and they can sometimes be useful for testing for malaria in between relapses because the antibodies your body produces against the malaria parasite during the relapse phase can stick around in the blood for weeks, or even months or years. Therefore these tests are not very useful for people in endemic areas (who may always have these antibodies, regardless of their current infection status) but for travelers who have been exposed a limited number of times, this test may be able to say whether you have at some stage been infected with P. vivax; together with your clinical history, this will provide strong evidence to your doctor that you might need to discuss the possibility of taking primaquine, the drug which can kill the dormant hypnozoites and prevent further relapse.

Trophozoites of Plasmodium Vivax

QUESTION

What should I take in this condition? After treatment I came to know that Rechocin should be taken for 6 months 2  weekly.

ANSWER

I am not sure I understand your question, but if you have been diagnosed with trophozoites of Plasmodium vivax in your blood, then you can be treated with normal anti-malarials (the World Health Organization recommends artemisinin-based combination therapies for first line treatment of uncomplicated malaria, but depending where you are, you might even just be able to take chloroquine), as these kill the blood stages of malaria. To prevent relapse, caused by hypnozoites dormant in the liver, you should talk to your doctor about the possibility of also taking a course of primaquine, which usually lasts 14 days. This drug is not suitable for people with G6DP deficiency, however, so you may need a test for this condition before you can take the treatment.

Malaria Testing

QUESTION

My daughter is in Kigoma, Tanzania and has the symptoms of Malaria. She was given Duo Cotecxin and it seems to have started making her feel better. But after reading up on all the different types of Malaria parasites I am wondering if a blood test reading at a clinic would be recommended or is it too late for an accurate reading now that she is on meds?

ANSWER

I am always very nervous about people given malaria medication without a proper blood test-based diagnosis. The symptoms of malaria can sometimes be very general, and I have recently seen some data from elsewhere in Tanzania whereby clinics are giving virtually everyone who comes in with a fever malaria medication, even if the blood tests are negative! This is a sure way to develop resistance to malaria drugs, plus exposes people to the potential side effects of medication that they may not need, while also failing to diagnose or treat them for whatever other condition they may also have.

In your daughter’s case, since she is feeling better, it may be that she did indeed have malaria. Regardless, now that she is taking the treatment, she should make sure to finish the full dose of pills. It still could also be worth going in for a blood test. In any case it will put your mind at rest, and if there are still traces of the parasite in her blood, then you will know for sure that she had malaria. Moreover, it might tell you which type of malaria she had. While P. falciparum is the most common form of malaria in sub-Saharan Africa, cases of other types, such as P. vivax and P. ovale, are being reported more and more frequently.

These two types can form liver stages (called hypnozoites) which can stay dormant for weeks, months or even years after the initial infection. During this period, the patient will experience no symptoms; then, when the hypnozoites activate and re-enter the blood again, the patient will get a “relapse” of the malaria symptoms. The only drug available to kill these liver stages is primaquine; as such, if your daughter is positively diagnosed with P. vivax or P. ovale malaria, she should be aware of the possibility of a relapse, and perhaps discuss with a doctor the possibility of taking primaquine.

I hope she recovers fully and enjoys her stay in Kigoma—I spent almost a month out there last year!

Long term health effects of malaria when young?

QUESTION

I’m trying to find out if having malaria at a young age can have long term effects on health.

Around 25 years ago when I was 4 years old I contracted malaria when living in central Africa. Unfortunately I do not know the type of malaria, only that I received medication and recovered without complications.

Over the last few years I’ve had a general feeling of poor health and fatigue. Blood tests indicate I have some level of liver damage but I’m at a loss for the cause.

Is there any chance of having picked up liver damage (or other long term effects) from contracting malaria at a young age?

ANSWER

There is little evidence for any long term complications associated with uncomplicated malaria infection. One thing to investigate might be the type of malaria you had as a child; Plasmodium vivax and Plasmodium ovale, while not as common as Plasmodium falciparum in Central Africa, both occur in this region, and differ from P. falciparum in that they can have a dormant liver stage.

While I still have not heard of liver problems being associated with dormant malaria parasites, it is conceivable that if you had one of these two types of malaria and did not have the liver stages treated, you might later feel some ill effects; relapse from P. vivax has been known to occur decades after the initial infection. The good news is that there is a drug available, called primaquine, which can kill these liver stages (known as hypnozoites). So, if you know you had P. vivax or P. ovale, you could mention this possibility to your doctor—prior to taking primaquine you should have a test for G6DP deficiency, as such as deficiency makes it dangerous to take this medication.

If you have ever taken anti-malaria medication, please take Malaria.com’s brief Malaria Medication Side-effects Survey: Treatment and Prophylaxis.

How is Malaria Treated

QUESTION

How is malaria treated?

ANSWER

This answer is copied from an earlier question about the various available cures for malaria.

Malaria can be cured with a number of different medications, depending on then type of malaria and how far the disease has been progressed.

For standard, non-complicated Plasmodium falciparum malaria, the World Health Organisation recommends use of artemisinin-based combination therapies (ACTs), such as Coartem. This is due to increasing levels of resistance to chloroquine in many parts of the world. Indeed, even though chloroquine is still used in many places as first-line treatment against P. vivax, P. malariae, P. ovale and P. knowlesi uncomplicated malaria, there is some evidence that resistance to this treatment is also emerging, for example in P. vivax in parts of south-east Asia.

In cases where malaria infection has progressed to a stage where oral administration of medication is not possible, or where cerebral symptoms are suspected, the usual treatment option is intravenous quinine.

In addition, P. vivax and P. ovale malaria parasites are able to produce forms (called hypnozoites) which can become dormant in liver hepatocyte cells after the blood stages of the infection have been cleared. These dormant forms can become reactivated weeks or even months or years after the initial infection, which is called a “relapse” of the infection. One drug, called primaquine, is able to kill these liver stages, and so patients with either of these types of malaria should also discuss the possibility of taking primaquine.

Apart from these first-line treatments, there are other medications which are used against malaria, both prophylactically as well as for treatment. These include orally-administered quinine, pyrimethamine, mefloquine, proguanil, atovaquone and sulfonamides.

 

Malaria Re-occurrence

QUESTION:

I’ve been infected with malaria vivax, for this i’ve taken the treatment for three days, after three days i don’t have any symptoms but after two days again I’m feeling the fever and abdominal pain which i’m having since the diagnosis is still persisting. Why is it happening? Are there any chances even after treatment for re-occurrence? My urine is yellow color but there is no jaundice?

ANSWER:

“Vivax” malaria, caused by the parasite Plasmodium vivax, is known for cyclical fevers every couple of days. As such, it may be that while the medication is working, you are still experiencing some mild symptoms as the infection is not completely cleared. For this reason, it is very important to take the full course of medication prescribed to you by your doctor; DO NOT stop taking it as soon as you feel better, as you might not have killed all of the malaria parasites in your blood, putting yourself at risk for the infection to persist. Alternatively, it might be that the strain of P. vivax you have is not responding to the medication you have been given; in parts of Papua New Guinea and Indonesia, for example, the local strains of P. vivax have been shown to have high levels of chloroquine resistance, which is usually used for treating P. vivax. If you are located in an area of known P. vivax resistance to chloroquine, your doctor should be able to recommend a different regimen of treatment to ensure that the infection is cured thoroughly. You should take a blood test after completing treatment to be sure that the parasite is no longer in your blood stream. In addition, P. vivax can produce dormant liver stages called hypnozoites that can remain within the liver hepatocyte cells and cause relapse or recurrence of the disease many weeks or months after the initial infection. To destroy these liver stages, and thus prevent relapse, you should ask your doctor about taking another drug once you have completed your initial treatment. This second drug is called primaquine, and will kill the P. vivax hepatocytes.