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FREQUENTLY ASKED QUESTIONS [FAQ's] Questions Q
1: "Why is Sickle Cell Anaemia only found in Black people?" Q
2: "Why do people with sickle cell anaemia not suffer from malaria?" Q
3: "Why then do Science teachers always talk about malaria and
sickle cell anaemia?" Q
4: "So what makes the difference between the sickle cell trait
phenotype on the one hand, and the sickle cell anemia and normal haemoglobin
phenotypes , on the other hand as far as malignant malaria is concerned?" Q
5: "So what really are these sickle cells?" Q
6: "Why are Scientists so excited about malaria and sickle cells?" Q
7: "Is this an example of the Natural Selection that they talk
about?"
Q 8: "What should one's attitude be regarding
adult sickle cell traits and malaria?" Q
9: "What is the difference between Sickle Cell Anaemia and Sickle
Cell Disease?" 'Sickle Cell Anaemia' is also sickle cell disease ('SS Phenotype'). The reason it is called sickle cell anaemia is because anaemia (low haemoglobin level) is the most obvious feature of the SS phenotype. Other haemoglobin genes can combine with sickle haemoglobin to cause sickle cell disease of varying degrees of severity, namely Haemoglbins D, E, G, K, O, Korle-Bu, Osu-Christiansborg, etc. Beta-Thalassaemia is not an abnormal haemoglobin gene (it is a gene for producing an insufficient amount of Normal haemoglobin), nor is Foetal Haemoglobin (which is Normal Haemoglobin for the baby in the womb, but which should disappear in adulthood). If Foetal Haemoglobin persists into adulthood it is known as Hereditary Persistence of Fetal Haemoglobin (HPFH) which can combine with sickle haemoglobin gene to cause disease. Similarly, a beta-thalassaemia gene can combine with Haemoglobin S to cause illness. So the sickle cell diseases can include the phenotypes SS (sickle cell anaemia), SC, SD, SE, SG, SK, SO, S Korle-Bu, SOsu-Christiansborg, SBeta-Thalassaemia, SFhereditary, etc. The various clinical presentations of the common phenotypes have been compared and contrasted in Konotey-Ahulu's book 'The Sickle Cell Disease Patient' [Reference 9]. Q
10: "How do I find out whether I have sickle cells or another haemoglobin
gene?" A 10: A simple test that can be done even in a little-equipped laboratory, involving placing a drop of blood on a glass slide, is all that is necessary to detect the presence of sickle cells. This simple Sickle Test is based on the fact that red blood cells which contain Haemoglobin S, can be made to alter their shape from round to sickle shape by adding a reducing agent to the blood [like a 2% solution of sodium meta-bisulphite], or by depriving the blood of oxygen through covering it on the slide using a cover-slip sealed round with vaseline. This primitive Test is still useful in rural areas in some countries. A quick method used to detect sicklers before a general anaesthetic is through a Solubility Test, using molarity phosphate buffer. The colour change that is used to detect Haemoglobin S, and which is useful in unmasking Sickle Cell Anaemia (SS) does not distinguish another Sickle Cell Disease like the SC phenotype (S abnormal, C abnormal) from the Sickle Cell Trait (AS - A normal, S abnormal) which is not a disease. Anaesthetists, please read that again and again until it sinks in, because there is a wealth of difference between anaesthetising an SC person, and an AS person. To think one is anaesthetising a Sickle Cell Trait (AS) when in fact an SC patient is lying on the operating table can make the difference between complications and a successful outcome. Remember, important though a 'Sickle Cell' Test is in revealing the presence or absence of Haemoglobin S, it is always necessary to do a Haemoglobin Electrophoresis to identify the true phenotype of a person who has not been transfused recently. Transfused blood in someone with abnormal haemoglobin is likely to confuse the person's true phenotype. For example, a sickle cell anaemia person (SS) who has recently received several units of normal blood will show A and S bands on electrophoresis, while an SC person will turn out to have 3 bands: A, S, and C. Haemoglobin electrophoresis will also reveal the presence of most other abnormal haemoglobins. [See below and Clinical/Scientific FAQ's]. Q
11: "What is sickle cell crisis?" A 11: Sickle cell crisis occurs when a significant number of the red blood cells of a patient with Sickle Cell Disease (no normal-haemoglobin gene inherited, ie SS or SC, or SD, or S beta-Thalassaemia, or. .) alter their shape from the usual round-shape to sickle-shape. People often thought that all the red cells flowing in the blood vessels of someone with sickle cell disease were distorted and sickled. No, the red cells are usually round and malleable like those of a person without Haemoglobin S. It is when circumstances make the body's internal environment lack oxygen, or get too hot, or too 'acidic', or too sluggish, that red blood cells with Haemoglobin S change shape into sickle-shape (or mini-cigar shape), clogging up the tiny vessels and causing severe pains wherever the clogging up occurs - around joints, in the abdomen, in the head, in the male organ (priapism), in the ribs, in the bones of the back, and limbs, etc.
Q 12: "What are these circumstances that can give
rise to sickle cell crisis?" A 12: Fever, fatigue, high altitude (as when some SS person embarks a plane at Accra [sea-level] and disembarks the next day at Addis Ababa or Nairobi [7-8,000 ft]), diarrhoea and vomiting causing dehydration, prolonged squatting or curling up in a chair for hours thereby trapping blood cells in the legs without benefit of oxygenation in the lungs [the so-called tourniquet effect - see July Person History on this website], underwater swimming, pregnancy and prolonged labour, smoking, alcohol, opiates like morphine and heroin which suppress breathing, severe exercise, the rainy season especially when caught in the rain, cold weather, some personal idiosyncrasies like 'eating rice and beans', severe asthmatic attack, infections of organs like the the lung (pneumonia), urinary tract and gall bladder. Malaria is the commonest cause of sickle cell crisis in African countries. Sore throat, ear ache, tooth ache, leg ulcers are other infections that can spark off a sickle cell crisis. Poorly administered general anaesthetic, and depriving the patient of fluids for hours before surgery can be dangerous. A "nil by mouth" notice for one who is booked for surgery, without giving fluids intravenously could lead to the sad observation later: "The operation was successful, but the patient developed a stroke." Patients should always keep a diary, to tell them what caused their crisis. When patients feel well, and are not in crisis, they are said to be in the steady state. Experienced Nurses like Marion McTair of The National Sickle Cell Society (UK), and some Clinicians very wisely advise their patients to keep a diary meticulously, enabling them to identify the causes and circumstances of their sickle crises. In over 4 decades of practice, I personally know of no condition in Clinical Medicine, where the 'prevention is better than cure' adage has saved the lives of so many hundreds. Many of my patients with Sickle Cell Disease have passed 50 years of age through keeping a careful diary, which led them to the conclusion that going to bed before 10 pm every single night, and drinking plenty of water, sometimes more than 4 Litres of water a day, had kept them out of crisis for years. Q
13: "Do
Sickle Cell Traits (AS phenotype, with A greater than S, eg A=60%, S=37%)
get into Sickle Cell Crisis like those with Sickle Cell Disease (SS,
SC, Sb-Thal, etc)?" A 13: No. If someone with 'Sickle Cell Trait' is found to develop sudden, severe musculo-skeletal pains like happens with Sickle Cell Anaemia, then the 'sickle trait diagnosis' as the cause of the problem is wrong. Look for another diagnosis. I have seen people referred to as 'Sickle Cell Trait' merely because the father is Sickle Test Positive, but the mother is not. "How can a person have Sickle Cell Disease when only one parent is a Sickler?", they ask. The answer is that, if the person has a sickle cell crisis, but the mother is 'Sickling Negative', then she will almost certainly be found to be 'POSITIVE' for Haemoglobin C or other mutant-haemoglobin gene which, together with the Haemoglobin S gene causes severe Ache/Ache disease like Sickle Cell Anaemia (SS). Read that again, and again: "If someone with 'Sickle Cell Trait' is found ..." Is that clear? "Sickle Negative" does not mean "Abnormal Haemoglobin Negative". Say that aloud. "Sickle Negative does not mean Abnormal Haemoglobin Negative". If the sickle cell test on someone is 'Negative', it does not mean the person is 'AA phenotype or Non-Ache/Non-Ache'. Sometimes even certain doctors insist that because Haemoglobin Electrophoresis shows 2 major bands - a Normal A band, together with the mutant S band, that makes it certain that they are dealing with a Sickle Cell Trait Phenotype. Not necessarily, for if the amount of S haemoglobin was quantified in someone in sickle cell crisis who showed Haemoglobins A and S on electrophoresis, then the amount of S will always be found to be greater than that of A haemoglobin, and that makes the person Sickle cell beta-Thalassaemia phenotype, (Two mutant genes for haemoglobin formation, namely an Ache/Ache Disease) and not Sickle Cell Trait (One mutant gene plus one normal gene). Read that again. "Sickle Negative does not mean 'Abnormal Haemoglobin Negative'..." Haemoglobin A which, when quantified, is less than Haemoglobin S, means a beta-thalassaemia gene. In the Sickle Cell Trait, the amount of sickle haemoglobin S is always less than that of normal Haemoglobin A. Is that clear? If you, the reader of this web site, have been having severe sickle cell crisis periodically, and you have been called 'sickle cell trait' merely because one of your parents was 'Sickle Cell Test Negative', then go back to your Doctor and ask for Haemoglobin Electrophoresis. You might find that you had a Sickle Cell Disease (Ache/Ache), like Sickle Cell beta-Thalassaemia (SA on electrophoresis, with S greater than A), or if you were athletic looking and you had a high haemoglobin level (like 15 g/dL or more), then you had Sickle Cell Haemoglobin C (SC phenotype, which is certainly not sickle Cell Trait). The common belief that when you have sickle cell disease you must also have anaemia, ie low haemoglobin level, is dangerously wrong. Sickle Cell Traits do not escape the consequences of incompetently-administered general anaesthesia, any more than those without sickle cells do. People with no abnormal haemoglobin whatever ie those with AA haemoglobin phenotype have been known to die under poorly administered general anaesthesia, such as when the doctor forgets to switch on the OXYGEN supply. These sad cases end up in a Coroner's Court. Should these circumstances of incompetently administered general anaesthesia be repeated with a Sickle Cell Trait person undergoing surgery, that patient would also die, but at post-mortem 'total sickling' would be reported. The patient would not be awake to report a 'sickle cell crisis', just as the unfortunate AA patients were unable to complain of lack of Oxygen before they died. Competently-administered general anaesthesia never threatened a Sickle Cell Trait as Consultant Anaesthetists Professor Kofi Oduro and Dr John Searle amply demonstrated. They administered general anaesthesia to 479 'sicklers' in Ghana over a period of 2 years, reporting their findings in the British Medical Journal 1972, Volume 4, pages 596-598 ['Anaesthesia in sickle cell states: A plea for simplicity.']. One of the reasons Anaesthetists are advised to give plenty of Oxygen preoperatively and post-operatively to any 'sickler' is that the correct diagnosis of 'Sickle Cell Trait' preoperatively is very poor. As mentioned above, the colour test used to unmask sickling does not distinguish between the SC phenotype (Ache/Ache), a disease-state which is notorious for fooling anaesthetists because of the patients' robust features and high haemoglobin status, and the Sickle Cell Trait (AS). SC-phenotype people suffer very badly when fluids are with-held before surgery, and their combined S & C haemoglobins solidify quicker than other haemoglobin combinations when things go wrong. I myself had once assumed that a healthy, robust man who died under anaesthesia for eye surgery in London was 'Sickle Cell Trait' until I met his AS widow with their SS and SC children. The mother had given her S gene to both daughters while the father's S and C genes were distributed between them. The man was not AS at all. He had Haemoglobin SC disease, and the colour sickle test had not distinguished between the Trait state (AS), and the Disease state (SC). For general anaesthesia therefore, my advice is to treat all sicklers as if they had the disease, and give plenty of Oxygen and fluids intravenously. [We shall come back to this again, and again. Watch for later instalments on sickle cells and flying. See also Chapter 30 in my 'The Sickle Cell Disease Patient', especially pages 362 to 371] Q
14: "But did not 4 American Army Recruits with sickle cell trait die
exercising at 4,000 feet?" A 14: No, they did not die from Sickle Cell Trait. This rumour began in 1970 when SR Jones, RA Binder, and EM Donowho Jr published in the New England Journal of Medicine, Volume 282, pages 323-325, an article entitled: "Sudden death in sickle cell trait" where they stated that "violent exercise and residence at a moderately high altitude (4,000 ft; 1,220 m)" was capable of precipitating a fatal sickling crisis in sickle cell trait carriers. I researched that article, and wrote to the British Medical Journal January 15 1972 (Volume 1, pages 177 -178, 1972): "Actually, in their paper entitled 'sudden death in sickle-cell trait' the authors relied on the 'SA' electrophoretic pattern without quantification of A2, A, or S in three of their cases, and in the fourth who did not even have haemoglobin electrophoresis they were content to call it sickle-cell trait because 'a sickle cell preparation at autopsy was positive'". This flawed publication is typical of many articles which have maligned sickle cell traits, some of whom competed at the Mexico Olympic Games at more than 7,000 ft above sea level and beat the whole world. The fact is that, in a place like southern Ghana where 1 in 5 perfectly healthy people have the sickle cell trait, we should expect to find that 1 in 5 of all doctors, 1 in 5 of all thieves, 1 in 5 of all soldiers, 1 in 5 of all lawyers, 1 in 5 of hill climbers at 4,000 feet, 1 in 5 of all sudden deaths, 1 in 5 of people vomiting blood, 1 in 5 of all athletes, 1 in 5 of all prostitutes, 1 in 5 of the 'Black Star' Football Team, 1 in 5 of the many past Heads of State, 1 in 5 of all diabetics, 1 in 5 of all fools, 1 in 5 of all heart failure patients, 1 in 5 of those with cerebral palsy, 1 in 5 of all stammerers or stutterers, 1 in 5 of all rogues, 1 in 5 of all Left-handed people, and 1 in 5 of those southern Ghanaians reading this website will be expected to have the Sickle Cell Trait (AS). In fact, I have already told readers of this website that my own father had Haemoglobin C Trait (AC) and my mother Sickle Trait (AS, see Genealogy Tree). So very common are these Traits. If a Ghanaian dropped down dead in the USA, there was a 1 in 5 chance that he would be Sickle Cell Trait, and if at autopsy the Pathologist found a Positive Sickling Test, would he be entitled to publish the phenomenon as a case of "sudden death in a sickle cell trait"? Thus linking sudden death with sickle cell trait? Certainly not! But that is what has been known to happen in the past. Even deaths of Blacks due to violence at the hands of unscrupulous Prison Officers have been known before to have been attributed to the 'Sickle Cell Trait'. The spate of journal articles linking all kinds of symptoms with the 'Sickle Cell Trait' had become so alarming that Professor James Bowman and his colleague Dr S Bernstein in Chicago (University of Illinois) were forced to exclaim that "persons with sickle cell trait will no longer be able to become ill or even die lest they find themselves subject of case report" (Bowman JE, Bernstein S. 'Caution about preliminary reports'. Pediatrics 1977; Volume 59: pages 639 - 640). As I write this FAQ, a young lady from the north of England contacted me to ask for advice regarding her frequent painful spasms due, she said, to 'Sickle Cell Trait'. She then added (in passing) that she was born with cerebral palsy, and was wheel chair bound. The message obviously had not got through to her that cerebral palsy (not sickle cell trait) was the cause of her severe painful spasms. [We shall keep coming back to this, because of the numerous queries regarding 'The Sickle Cell Trait'. Meanwhile, a bright student reading this material is entitled to ask the question: "But is there not a disease in Ghana of which it is not true to say '1 in 5 of the sufferers will be found to have the Sickle Cell Trait (AS)'?" Answer: Yes, there is - Cerebral malaria. Professor JOO Commey and Colleagues in Accra ('Cerebral malaria in Accra, Ghana' Ghana Medical Journal, 1980, Volume 19, pages 68-72), confirming the known fact that sickle cell trait children (AS phenotype) were not represented in those dying from cerebral malaria, decided in 1985/86 to look at the phenotypes of 30 consecutive cases of cerebral malaria admitted to the Korle Bu Teaching Hospital. In a population where 1 in 5 of all consecutive hospital admissions would be expected to be Sickle Cell Trait (AS), "the results showed conclusively that there was not one sickle cell trait phenotype where at least four were expected" (Konotey-Ahulu in 'The Sickle Cell Disease Patient', page 95). That did not mean Sickle Cell Traits were not infected by the malarial parasite; what it meant was that they were not being admitted to hospital dying from cerebral malaria because not enough parasitized red cells matured to release huge numbers of malarial parasites to invade the brain. From this point of view the Sickle Cell Trait had protected the children from cerebral malaria. - See FAQ 2 -9] Q
15: "What about urinating blood, which occurs frequently in sickle cell
traits?" A 15: Urinating blood does not occur frequently in sickle cell traits. First of all, we must remember that millions of people pass blood in the urine all over the world. If sickle cell traits did not ever pass blood in the urine from the same conditions that caused other people to pass blood in the urine (a symptom known as haematuria) they would be super human. Many articles purporting to describe haematuria in 'sickle cell traits' were, in fact, describing Sickle Cell haemoglobin C Disease patients (Ache/Ache SC phenotype) where "frequently" in my experience has been quantified as 2%, or 1 in 50. If a sickling POSITIVE person, with very high haemoglobin level of 16 or 17 g/dL, was found urinating blood I knew some doctors who would refer them to me as cases of 'Sickle Cell Trait'. The very high haemoglobin level was thought incompatible with Sickle Cell Disease. "Sickle Cell Trait it must be", they would say. When, however, haemoglobin electrophoresis was performed these "trait" people were most often found to have Sickle Cell Disease (SC), or if the haemoglobin level was less, they were SS or Sbeta-Thalassaemia. One eminent American Pathologist (an expert in post-mortem material) made the following statement: "Of the Hb SS, SC, Sbeta-Thalassaemia and AS states, gross haematuria is most frequently observed in Hb AS". To clinicians working in populations where 1 in 5 healthy persons, including international athletes, have the sickle cell trait (AS, with A greater than S) this statement is grossly incorrect, for that was not their experience. When that particular Pathologist (whom I knew personally) began his medical practice 'Haemoglobin C' had not been discovered. The SC phenotype would be known to him as 'Sickle Cell Trait', and he might unconsciously be carrying his previous terminology into the era of haemoglobin electrophoresis. It is desirable always to quantify the incidence of symptoms in sickle cell states. To tell even sickle cell disease patients (Ache/Ache) that they are certainly going to get haematuria is also not correct. They must always be told the proportion of patients of which sex, which phenotype, etc that get which symptom. For example, of 1,346 consecutive Sickle Cell Disease (Ache/Ache) patients seen by me, 13 of 642 females (2.0%) and 16 of 704 males (2.3%) had haematuria. There is no statistical difference in sex incidence. But there is significant statistical age group distribution with haematuria incidence. None due to sickling occurred below 5 years of age, "and the greatest number (37.9% of all haematuria cases) occurred in the 20-24 age group. No cases were found in the 44 patients aged 45 years and above. Of 1,319 consecutive patients at the Sickle Clinic 13 (2.2%) of 598 SS patients and 15 (2.5%) of 588 SC patients had haematuria. None of 148 other patients complained of passing blood in the urine. Thus, on the occasions when haematuria was found in Accra over 6 consecutive years in the Sickle Cell Clinic, young adults and child-bearing women would seem to be most affected, and then only the sickle cell disease patients (SS & SC phenotypes) were involved - The Sickle Cell Disease Patient, Chapter 17. On the other hand, haematuria in sickle cell traits as seen by Clinicians and not deduced from post-mortem material is very rare. For while 1 in 50 of sickle cell disease patients seen by the same Clinician (Dr Konotey-Ahulu) have been known to complain of passing blood in the urine "There is absolutely no doubt that the incidence of renal haematuria from in vivo sickling in sickle cell traits is very rare, being less than 1 in 1000 sickle traits per lifetime (definition of 'lifetime' is taken as the duration of life of the adult who is investigated). In other words", Dr Konotey-Ahulu goes on, "if one investigated 10,000 sickle trait adults for haematuria during their lifetime,...one would find less than 10 renal infarcts due to sickle cell trait". Continuing to come back to my own family, to say Dr Konotey-Ahulu's AS mother never passed blood in the urine during her entire life of 89 years adds little to the argument, but it is just mentioned for the record. The Sickle Cell Trait/haematuria over-emphasis, according to Dr Konotey-Ahulu, "is directly due to our ignorance of the existence of Haemoglobin C" until comparatively recently. Some reports, often quoted, like that of Goodwin and colleagues in Urology 1950, Volume 63, pages 79-96 entitled: 'Haematuria and sickle cell disease' were published before the discovery of haemoglobin C. The authors would have wrongly identified SC phenotype (Ache/Ache) as Sickle Cell Trait AS (Norm/Ache) because C haemoglobin (which does not sickle) was not discovered until 1951. Other conditions precipitating bleeding in the sickle cell trait kidney should always be looked for as, for example, in the patient of Weingler and Colleagues where bleeding from the kidney was associated with Von Willebrand's disease ('Gross haematuria associated with sickle cell trait and Von Willebrand's disease' - Journal of Urology 1979, Volume 122, pages 136-137.)" Q
16: "So what would we do with a known Sickle Cell Trait (Hb A proportion
greater than Hb S) passing blood in the urine?". A
16:
How did I manage such a patient in the past? First, I said to myself,
look for what could cause bleeding in anybody else. In the tropics I
made sure Bilharzia (Schistosomiasis haematobium) was not the problem.
When it was, I treated it with Metrifonate or Praziquantel. Other causes
of blood in the urine were quickly excluded, like bacterial infection
(Eschericia coli, or Proteus, or Tuberculosis, etc), or stones in the
kidney, or tumour in the urinary tract, or (in the male) prostate problems.
Even in patients who did not have sickle cells, there would always be
some for whom no cause for blood in the urine could be found. In these,
as in the case of those who are Sickling 'Positive', I went on to find
out whether someone kicked them in the back, or they had a car accident,
or they were taking blood thinning drugs like Aspirin, or Anticoagulants,
or platelet reducing agents, all of which could cause bleeding. If an
examination of the inside of the bladder (cystoscopy) showed blood oozing
from the Left ureter, (for the Left kidney almost always bled first
in sickle cell states), and kidney scans, with an intravenous urogram
(pyelography) revealed that part of the kidney was 'infarcted' then,
and only then, should it be assumed that this was 'sickle cell haematuria'.
Apart from infection, conditions like dehydration, haemo-concentration,
enlarged spleens, and pregnancy were the circumstances that I have known
to cause sickle cell infarction, which led to bleeding. I have known
flying long distances (over 8 hours) to precipitate renal bleeding in
a Sickle Cell Haemnogliopbin C Disease patient (SC phenotype) but I
have never known flying to cause this in the AS phenotype. Look also
for a combination of factors. When bleeding occurred, it was found (as
demonstrated on page 213b, of 'The Sickle Cell Disease Patient') that
the urine from the bleeding kidney had a heavy growth of bacteria. Although
true renal infarction is rare (and remember it happens to those without
sickle cells as well), when it occurs even in one sickle cell trait,
the incidence is 100% in that one person in whom it occurs. It is no
comfort to the sufferer for the Doctor to say "it is extremely rare".
For example, Professor Yeboah and Colleagues at The Korle Bu Teaching
Hospital found, between November 1972 and June 1975, that of 202 patients
referred to them at the Urology Department with haematuria, only 9 (2%)
were sickle-related, and these were all of the SC phenotype. (Yeboah
and colleagues: 'The causes and management of haematuria in Accra, Ghana'.
Ghana Medical Journal 1975, Volume 14, pages 299-306). For these 9 individuals,
the condition was not rare. How were they managed? Treatment of established
renal infarction is bed rest, and plenty of fluids (up to 12 Litres
intravenously of Normal Saline has been given before, in 24 hours),
with sterilisation of the urine with the appropriate antibiotic. This
approach, with blood transfusion, in the very severe cases, has always
been successful in stopping the bleeding in most patients. Surgery has
little place in sickle cell kidney bleeding management. It requires
to be pointed out that people have had one or both their kidneys removed
rather unnecessarily. There needs to be great caution. Having said that,
1 in 5 of all malignant kidney tumour patients in southern Ghana should
be found to have the Sickle Cell Trait. If the Surgeon decided to remove
the kidney, it was because of the carcinoma, and not because of the
sickle state. In the most severe cases of sickle cell haematuria in
Ghanaian SC patients epsilon-amino-caproic acid (EACA) was tried by
Bernard Ribeiro, Professor JMK Quartey, and myself with dramatic results
[Ribeiro B, Quartey JMK, Konotey-Ahulu FID, 1979. 'Hydration and epsilon
amino caproic acid as quick solution to haematuria in sickle cell disease.'
Our procedure was: "5 g - EACA intravenously over 30 minutes followed
by 1 g per hour until bleeding stopped. Correction of dehydration, with
alkalination of urine, and treatment of infection should be tried before
ACA is used." page 210 in 'The Sickle Cell Disease Patient', FAQ Reference
9] Remember that any symptomatic Sickle Cell Trait (AS) needs thorough
investigation. Never should a symptom be attributed to the 'Sickle Cell
Trait' without posing the question: "Could a non-sickler, ie AA (Norm/Norm)
not have the same problem - a stroke, vomiting in an aeroplane, stomach
pains, convulsions, osteo-arthritis, miscarriages, etc as this Sickle
Trait has?" If, on the other hand, the symptoms are those of sickle
cell disease (acute cold-season rheumatism, hip necrosis, multiple pigment
gall stones, haemolytic jaundice, leg ulcers, acute visual problems,
splenic pain, etc) then what appears to be a genuine 'AS' diagnosis
needs looking at again as Dr Witkowska and Colleagues in Canada did
and, lo and behold, discovered a new haemoglobin masquerading as normal
Haemoglobin A. In other words their 'AS' was not-AS at all, but an entirely
new haemoglobin plus haemoglobin S, the combination producing an Ache/Ache
situation rather than the expected Norm/Ache phenotype 'AS'. [Witkowska
HE, Lubin BH, Beuzard Y and colleagues: "Sickle cell disease in a patient
with sickle cell trait and compound heterozygosity with haemoglobin
Quebec-Chori". New England Journal of Medicine 1991; Volume 325, pages
1150-1154.]. Students researching these matters are advised also to
look up my comments on this article: Konotey-Ahulu FID. "Beware of symptomatic
sickle-cell traits" Lancet 1992, Volume 339, page 555 (in which I pointed
out that the 'Sickle Cell Trait AS' may not be true sickle trait, and
the 'Haemoglobin C Trait AC' may also be something else, as the "A"
has been shown could stand for haemoglobin Quebec-Chori.] |
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