Transcription
We have been talking about point kilo sites, or abnormally shaped red blood cells, for a little while now. Let's turn our attention to red blood cell inclusions. Today's topic is basophilic stippling. Now pay attention: I'm talking about basophilic stippling of the red blood cells, not the basophils. Basophilic stippling basically describes the stippling; it's a blue stippling of the red blood cell, not the basophil, which is one of the white blood cells. So basophilic stippling, also known as punctate basophilia, punctate because it's like dots, is one of the red blood cell inclusions. They are basophilic dots or granules in the red blood cell cytoplasm. These basophilic granules basically are a residue consisting of ribosomes, degrading mitochondria, and other stuff. Basophilic stippling means there is a problem with erythropoiesis, or new formation of red blood cells. The most significant cause of basophilic stippling is lead poisoning. Please never forget this for your exam.
When do we see basophilic stippling of the red blood cell? Lead poisoning, of course. And lead poisoning is described as microcytic anemia with coarse basophilic stippling. You will find this on the blood film or the peripheral smear. What else? We have thalassemia; we have hemolytic anemia, such as sickle cell anemia; and of course, thalassemia can lead to hemolytic anemia. Megaloblastic anemia, such as B12 deficiency, folate deficiency, etc., also myelodysplastic syndrome, or MDS. MDS is an intermediary gateway between normal and leukemia, acute myeloid leukemia. The intermediate state is called MDS, and we will discuss this later. Since basophilic stippling in cases of lead poisoning is very high yield for your exam, let's talk about lead poisoning.
Basically, in normal cells, you have your ribosome. There is an enzyme called ribonuclease, or RNAse, that degrades the ribosome, or breaks it down into degradation products. In lead poisoning, however, this enzyme is denatured by lead. So lead will destroy this enzyme. Now, ribosomes cannot be destroyed or degraded, so ribosomes will build up and they will persist in your red blood cell, and this is called basophilic stippling of the red blood cell.
Now let's give this case a shot. Please pause, read it, try to answer it, and come back. Okay, welcome back. Six-year-old boy; his parents are complaining of deteriorating school performance. He is also tired, irritable; he has abdominal pain, constipation; sometimes he vomits. They live in an old house built in the 1950s. This is important, why? Houses built before 1978 in the United States contained lead in the paint. In 1978, the United States federal government, especially the Environmental Protection Agency, or EPA, prohibited the use of lead in paint. Chips inside the houses, to paint the walls. So before that, maybe the house has lead in it. So, for example, the kid is lethargic, pale conjunctiva, and fatigued. This is an email systolic ejection murmur; could be a flow murmur because anemia causes a hyperdynamic circulation. This is not an organic murmur due to a valve problem; this is a flow murmur due to overflow. It takes a gate. So neurological problem, abdominal tenderness on deep palpation. Lab results: hemoglobin is nine—this is low; hematocrit—this is low; MCV—this is low. So here we have anemia, and this anemia is microcytic. So we have microcytic anemia. On the peripheral smear, using the right stain, we found this. Using the Prussian blue stain, we found this. What's that? This is basophilic stippling of the red blood cell. How about this? This is the ringed sideroblasts in sideroblastic anemia, as we have discussed before in a previous video. This is due to what? This is due to lead poisoning, okay, because lead destroys your mitochondria. What's the most likely diagnosis? Lead poisoning. Yes. Alcoholism? No, very unlikely. Child abuse? Child abuse can lead to deteriorating school performance, yes; fatigue, okay; irritability, maybe; lethargy, okay. But child abuse will never lead you to have this in your blood smear, okay. Please. How about the next step? Do you call the Child Protective Services? No, because it's very unlikely this is child abuse, unless these parents are making the kid eat the wall, which is pretty unlikely. Marrow biopsy? No. There is no need to measure blood lead level. Of course, this is the answer. About number three, what's the treatment of lead poisoning? Is it gastric lavage? No, because this is a chronic lead exposure. Deferoxamine is used to treat iron toxicity or iron overload. EDTA and BAL? Yes, this is the treatment. BAL is dimercaprol, and EDTA, EDTA. Dia mine teacher acidic acid. Oh, okay. That's it for today. Please consider subscribing, and I'll see you in the next video. Thank you.