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Methemoglobinemia can be treated with supplemental oxygen and methylene blue 1% solution (10 mg/ml) 1 to 2 mg/kg administered intravenously slowly over five minutes. Although the response is usually rapid, the dose may be repeated in one hour if the level of methemoglobin is still high one hour after the initial infusion. Methylene Blue inhibits monoamine oxidase and serotonin toxicity can occur if taken with an SSRI (selective serotonin reuptake inhibitor) medicine.
Methylene blue restores the iron in hemoglobin to its normal (reduced) oxygen-carrying state. This is achieved by providing an artificial electron acceptor (such as methylene blue or flavin) for NADPH methemoglobin reductase (RBCs usually don't have one; the presence of methylene blue allows the enzyme to function at 5× normal levels). The NADPH is generated via the hexose monophosphate shunt.
Genetically induced chronic low-level methemoglobinemia may be treated with oral methylene blue daily. Also, vitamin C can occasionally reduce cyanosis associated with chronic methemoglobinemia but has no role in treatment of acute acquired methemoglobinemia. Diaphorase normally contributes only a small percentage of the red blood cell's reducing capacity, but can be pharmacologically activated by exogenous cofactors (such as methylene blue) to 5 times its normal level of activity.
Methemoglobinemia may be acquired. Classical drug causes of methemoglobinaemia include antibiotics (trimethoprim, sulfonamides, and dapsone), local anesthetics (especially articaine, benzocaine, and prilocaine), and aniline dyes, metoclopramide, rasburicase, chlorates, and bromates. Ingestion of compounds containing nitrates (such as the patina chemical bismuth nitrate) can also cause methemoglobinemia.
In otherwise healthy individuals, the protective enzyme systems normally present in red blood cells rapidly reduce the methemoglobin back to hemoglobin and hence maintain methemoglobin levels at less than one percent of the total hemoglobin concentration. Exposure to exogenous oxidizing drugs and their metabolites (such as benzocaine, dapsone, and nitrates) may lead to an increase of up to a thousandfold of the methemoglobin formation rate, overwhelming the protective enzyme systems and acutely increasing methemoglobin levels.
Infants under 6 months of age have lower levels of a key methemoglobin reduction enzyme (NADH-cytochrome b5 reductase) in their red blood cells. This results in a major risk of methemoglobinemia caused by nitrates ingested in drinking water, dehydration (usually caused by gastroenteritis with diarrhea), sepsis, or topical anesthetics containing benzocaine or prilocaine. Nitrates used in agricultural fertilizers may leak into the ground and may contaminate well water. The current EPA standard of 10 ppm nitrate-nitrogen for drinking water is specifically set to protect infants. Benzocaine applied to the gums or throat (as commonly used in baby teething gels, or sore throat lozenges) can cause methemoglobinemia.
Sideroblastic anemias are often described as responsive or non-responsive in terms of increased hemoglobin levels to pharmacological doses of vitamin B.
1- Congenital: 80% are responsive, though the anemia does not completely resolve.
2- Acquired clonal: 40% are responsive, but the response may be minimal.
3- Acquired reversible: 60% are responsive, but course depends on treatment of the underlying cause.
Severe refractory sideroblastic anemias requiring regular transfusions and/or that undergo leukemic transformation (5-10%) significantly reduce life expectancy.
Ringed sideroblasts are seen in the bone marrow.
The anemia is moderate to severe and dimorphic. Microscopic viewing of the red blood cells will reveal marked unequal cell size and abnormal cell shape. Basophilic stippling is marked and target cells are common. Pappenheimer bodies are present in the red blood cells. The mean cell volume is commonly decreased (i.e., a microcytic anemia), but MCV may also be normal or even high. The RDW is increased with the red blood cell histogram shifted to the left. Leukocytes and platelets are normal. Bone marrow shows erythroid hyperplasia with a maturation arrest.
In excess of 40% of the developing erythrocytes are ringed sideroblasts. Serum iron, percentage saturation and ferritin are increased. The total iron-binding capacity of the cells is normal to decreased. Stainable marrow hemosiderin is increased.
Diagnosis of inherited hypoprothrombinemia, relies heavily on a patient's medical history, family history of bleeding issues, and lab exams performed by a hematologist. A physical examination by a general physician should also be performed in order to determine whether the condition is congenital or acquired, as well as ruling out other possible conditions with similar symptoms. For acquired forms, information must be taken regarding current diseases and medications taken by the patient, if applicable.
Lab tests that are performed to determine diagnosis:
1. Factor Assays: To observe the performance of specific factors (II) to identify missing/poorly performing factors. These lab tests are typically performed first in order to determine the status of the factor.
2. Prothrombin Blood Test: Determines if patient has deficient or low levels of Factor II.
3. Vitamin K1 Test: Performed to evaluate bleeding of unknown causes, nosebleeds, and identified bruising. To accomplish this, a band is wrapped around the patient's arm, 4 inches above the superficial vein site in the elbow pit. The vein is penetrated with the needle and amount of blood required for testing is obtained. Decreased vitamin K levels are suggestive of hypoprothrombinemia. However, this exam is rarely used as a Prothrombin Blood Test is performed beforehand.
The diagnosis of this condition can be done via the following:
- Flow cytometry
- Bleeding time analysis
In general on acid electrophoresis in order of increasing mobility are hemoglobins F, A=D=G=E=O=Lepore, S, and C.
This is how abnormal hemoglobin variants are isolated and identified using these two methods. For example, a Hgb G-Philadelphia would migrate with S on alkaline electrophoresis and would migrate with A on acid electrophoresis, respectively
use of iso electric focusing to determine quantitative differences in globin chain synthesis and high performance liquid chromatography that separates hemoglobins based on their various affinities for the column
In general on alkaline electrophoresis in order of increasing mobility are hemoglobins A2, E=O=C, G=D=S=Lepore, F, A, K, J, Bart's, N, I, and H.
In general a sickling test (sodium bisulfite) is performed on abnormal hemoglobins migrating in the S location to see if the red cells precipitate in solution.
A 28 month old girl, showed symptoms from 8 months of age and consisted of complaints of painful bruises over lower limbs, and disturbed, painful sleep at night. Family history revealed older brother also suffered similar problems and died at age of two years possibly due to bleeding - no diagnosis was confirmed. Complete blood count and blood smear was determined as normal. No abnormality in fibrinogen, liver function test, and bleeding time. However, prothrombin levels were less than 1% so patient was transfused with fresh frozen plasma (FFP). Post transfusion methods, patient is now 28 months old and living healthy life. The only treatment that is needed to date is for the painful bruises, which the patient is given FFP every 5-6 weeks.
Twelve day old boy admitted for symptoms consisting of blood stained vomiting and dark colored stool. Upon admission into hospital, patient received vitamin K and FFP transfusion. No family history of similarity in symptoms that were presented. At 40 days old, patient showed symptoms of tonic posturing and constant vomiting. CT scan revealed subdural hemorrhage, and other testing showed low hb levels of 7%, platelets at 3.5 lakhs/cu mm. PT examination was 51 seconds and aPTT at 87 seconds. Prothrombin activity levels were less than 1%. All other exams revealed no abnormalities. Treatment methods included vitamin K and FFP, as well as ventilator support and packed red blood cell transfusion (PRBC). At half a year of age, condition consisted of possible poor neurological outcome secondary to CNS bleeding. Treatment of very frequent transfusion was needed for patient.
Recent study illustrated a patient with 2 weeks of continuous bleeding, with presence of epistaxis, melena, hematuria, and pruritic rash with no previous bleeding history. Vitals were all within normal range, however, presence of ecchymoses was visible in chest, back and upper areas. Lab exams revealed prolonged prothrombin time (PT) of 34.4 and acquired partial thromboplastin time (aPTT) of 81.7, as well as elevated liver function tests. Discontinuation of atorvastatin, caused liver enzymes to go back to normal. Treatment of vitamin K, antibiotics, and fresh frozen plasma (FFP) did not have an impact on coagulopathy. Mixing of PT and aPTT was performed in order to further evaluate coagulopathy and revealed no correction. Factor activity assays were performed to determine the presence of a specific one. Testing revealed that factor II activity could not be quantified. Further studies showed that acquired factor II inhibitor was present without the lupus anticoagulant, with no clear cause associated with the condition. Aimed to control bleeding and getting rid of the inhibitor through directly treating the underlying disease or through immunosuppressive therapy. Corticosteroids and intravenous immunoglobulin improved the PT and aPTT. Did not improve bleeding conditions until treatment of transfusion with activated PCC. Treatment of inhibitor required Rituximab, which was shown to increase factor II levels to 264%. Study shows that when a patient with no history of coagulopathy presents themselves with hemorrhagic diathesis, direct testing of a factor II inhibitor should be performed initially.
Blood tests are neede to differentiate FVII deficiency from other bleeding disorders. Typical is a discordance between the prolonged prothrombin time (PT) and normal levels for the activated partial thromboplastin time (APTT). FVII levels are <10IU/dl in homozygous individuals, and between 20-60 in heterozygous carriers. The FCVII: C assay supports the diagnosis.
The FVII gene (F7) is found on chromosome 13q34. Heterogeneous mutations have been described in FVII deficient patients.
The condition is diagnosed by blood tests in the laboratory when it is noted that special blood clotting test are abnormal. Specifically prothrombin time (PT) or activated partial thromboplastin time(aPTT) are prolonged. The diagnosis is confirmed by an assay detecting very low or absent FXII levels.
The FXII (F12) gene is found on chromosome 5q33-qter.
In hereditary angioedema type III an increased activity of factor XII has been described.
In congenital FXII deficiency treatment is not necessary. In acquired FXII deficiency the underlying problem needs to be addressed.
There are several treatments available for factor VII deficiency; they all replace deficient FVII.
1. Recombinant FVIIa concentrate (rFVIIa) is a recombinant treatment that is highly effective and has no risk of fluid overload or viral disease. It may be the optimal therapy.
2. Plasma derived Factor VII concentrate (pdFVII) : This treatment is suitable for surgery but can lead to thrombosis. It is virus attenuated.
3. Prothrombin complex concentrate (PCC) containing factor VII: this treatment is suitable for surgery, but has a risk of thrombosis. It is virus attenuated.
4. Fresh frozen plasma (FFP): This is relatively inexpensive and readily available. While effective this treatment carries a risk of blood-borne viruses and fluid overload.
Diagnosis of acquired dysfibrinogenemia uses the same laboratory tests that are used for congenital dysfibrinogenemia plus evidence for an underlying causative disease.
Platelet storage pool deficiency has no treatment however management consists of antifibrinolytic medications if the individual has unusual bleeding event, additionally caution should be taken with usage of NSAIDS
The type of treatment depends on the severity of the patient’s bone marrow failure disease. Blood transfusion is one treatment. Blood is collected from volunteer donors who agree to let doctors draw blood stem cells from their blood or bone marrow for transplantation. Blood that is taken straight from collected blood stem cells is known as peripheral blood stem cell donation. A peripheral stem cell donor must have the same blood type as the patient receiving the blood cells. Once the stem cells are in the patient’s body through an IV, the cells mature and become blood cells. Before donation, a drug is injected into the donor, which increases the number of stem cells into their body. Feeling cold and lightheaded, having numbness around the mouth and cramping in the hands are common symptoms during the donation process. After the donation, the amount of time for recovery varies for every donor, “But most stem cell donors are able to return to their usual activities within a few days to a week after donation”.
Treatment of asymptomatic congenital dysfibrinogenemia depends in part on the expectations of developing bleeding and/or thrombotic complications as estimated based on the history of family members with the disorder and, where available, determination of the exact mutation causing the disorder plus the propensity of the particular mutation type to develop these complications. In general, individuals with this disorder require regular follow-up and multidiscipline management prior to surgery, pregnancy, and giving childbirth. Women with the disorder appear to have an increased rate of miscarriages and all individuals with fibrinogen activity in clotting tests below 0.5 grams/liter are prone to bleeding and spontaneous abortions. Women with multiple miscarriages and individuals with excessively low fibrinogen activity levels should be considered for prophylaxis therapy with fibrinogen replacement during pregnancy, delivery, and/or surgery.
There are several treatments available for bleeding due to factor X deficiency, however a specifi FX concentrate is not available (2009).
1. Prothrombin complex concentrate (PCC) supplies FX with a risk of thrombosis.
2. Fresh frozen plasma (FFP): This is relatively inexpensive and readily available. While effective this treatment carries a risk of blood-borne viruses and fluid overload.
3. If vitamin K levels are low, vitamin K can be supplied orally or parenterally.
Treatment of FX deficiency in amyloidosis may be more complex and involve surgery (splenectomy) and chemotherapy.
Blood tests are needed to differentiate FX deficiency from other bleeding disorders. Typical are normal thrombin time, prolonged prothrombin time (PT) and prolonged partial thromboplastin time(PTT). FX antigen and its coagulant activity can be used to classify the severity of the condition:
1. Type I has low levels of FX antigen and activity.
2. Type II has low coagulant activity but normal or borderline FX antigen levels.
The FX (F10) gene is found on chromosome 13q34. Heterogeneous mutations have been described in FX deficient patients.
The diagnosis of the disease is mainly clinical (see diagnostic criteria). A laboratory workup is needed primarily to investigate for the presence of associated disorders (metabolic, autoimmune, and renal diseases).
- Every patient should have a fasting blood glucose and lipid profile, creatinine evaluation, and urinalysis for protein content at the first visit, after which he/she should have these tests on a regular basis.
- Although uncommon, lipid abnormalities can occur in the form of raised triglyceride levels and low high-density lipoprotein cholesterol levels.
- Patients usually have decreased serum C3 levels, normal levels of C1 and C4, and high levels of C3NeF (autoantibody), which may indicate the presence of renal involvement.
- Antinuclear antibodies (ANA) and antidouble-stranded deoxyribonucleic acid (DNA) antibodies have reportedly been observed in some patients with acquired partial lipodystrophy.
- A genetic workup should be performed if the familial form of lipodystrophy is suggested.
Laboratory work for associated diseases includes:
- Metabolic disease - fasting glucose, glucose tolerance test, lipid profile, and fasting insulin to characterize the insulin resistance state; free testosterone (in women) to look for polycystic ovary syndrome.
- Autoimmune disease - ANA, antidouble-stranded DNA, rheumatoid factor, thyroid antibodies, C3, and C3NeF.
As a confirmatory test, whole-body MRI usually clearly demonstrates the extent of lipodystrophy. MRI is not recommended on a routine basis.
The two most common signs and symptoms of bone marrow failure are bleeding and bruising. Blood may be seen throughout the gums, nose or the skin, and tend to last longer than normal. Children have a bigger chance of seeing blood in their urine or stools, which results in digestive problems with an unpleasant scent. Individuals with this condition may also encounter tooth loss or tooth decay. Chronic fatigue, shortness of breath, and recurrent colds can also be symptoms of bone marrow failure.
In hospitalised patients who develop respiratory symptoms and fever, one should consider the diagnosis. The likelihood increases when upon investigation symptoms are found of respiratory insufficiency, purulent secretions, newly developed infiltrate on the chest X-Ray, and increasing leucocyte count. If pneumonia is suspected material from sputum or tracheal aspirates are sent to the microbiology department for cultures. In case of pleural effusion thoracentesis is performed for examination of pleural fluid. In suspected ventilator-associated pneumonia it has been suggested that bronchoscopy(BAL) is necessary because of the known risks surrounding clinical diagnoses.
Central cyanosis is often due to a circulatory or ventilatory problem that leads to poor blood oxygenation in the lungs. It develops when arterial oxygen saturation drops to ≤85% or ≤75%.
Acute cyanosis can be as a result of asphyxiation or choking, and is one of the definite signs that respiration is being blocked.
Central cyanosis may be due to the following causes:
1. Central nervous system (impairing normal ventilation):
- Intracranial hemorrhage
- Drug overdose (e.g. heroin)
- Tonic–clonic seizure (e.g. grand mal seizure)
2. Respiratory system:
- Pneumonia
- Bronchiolitis
- Bronchospasm (e.g. asthma)
- Pulmonary hypertension
- Pulmonary embolism
- Hypoventilation
- Chronic obstructive pulmonary disease, or COPD (emphysema)
3. Cardiovascular diseases:
- Congenital heart disease (e.g. Tetralogy of Fallot, right to left shunts in heart or great vessels)
- Heart failure
- Valvular heart disease
- Myocardial infarction
4. Blood:
- Methemoglobinemia * Note this causes "spurious" cyanosis, in that, since methemoglobin appears blue, the patient can appear cyanosed even in the presence of a normal arterial oxygen level.
- Polycythaemia
- Congenital cyanosis (HbM Boston) arises from a mutation in the α-codon which results in a change of primary sequence, H → Y. Tyrosine stabilises the Fe(III) form (oxyhaemoglobin) creating a permanent T-state of Hb.
5. Others:
- High altitude, cyanosis may develop in ascents to altitudes >2400 m.
- Hypothermia
- Obstructive sleep apnea
A review published in 2004, which was based on 35 patients seen by the respective authors over 8 years and also a literature review of 220 cases of acquired partial lipodystrophy (APL), proposed an essential diagnostic criterion. Based on the review and the authors experience, they proposed that APL presents as a gradual onset of bilaterally symmetrical loss of subcutaneous fat from the face, neck, upper extremities, thorax, and abdomen, in the "cephalocaudal" sequence, sparing the lower extremities. The median age of the onset of lipodystrophy was seven years. Several autoimmune diseases, in particular systemic lupus erythematosus and dermatomyositis, were associated with APL. The prevalence rates of diabetes mellitus and impaired glucose tolerance were 6.7% and 8.9%, respectively. Around 83% of APL patients had low complement 3 (C3) levels and the presence of polyclonal immunoglobulin C3 nephritic factor. About 22% of patients developed membranoproliferative glomerulonephritis (MPGN) after a median of about 8 years following the onset of lipodystrophy. Compared with patients without renal disease, those with MPGN had earlier age of onset of lipodystrophy (12.6 ± 10.3 yr vs 7.7 ± 4.4 yr, respectively; p < 0.001) and a higher prevalence of C3 hypocomplementemia (78% vs 95%, respectively; p = 0.02).
The adipose stores of the gluteal regions and lower extremities (including soles) tend to be either preserved or increased, particularly among women. Variable fat loss of the palms, but no loss of intramarrow or retro-orbital fat, has been demonstrated.
Cyanosis is defined as the bluish or purplish discolouration of the skin or mucous membranes due to the tissues near the skin surface having low oxygen saturation. Based on Lundsgaard and Van Slyke's work, it is classically described as occurring if 5.0 g/dL of deoxyhemoglobin or greater is present. This was based on an estimate of capillary saturation based on a mean of arterial versus peripheral venous blood gas measurements. Since estimation of hypoxia is usually now based either on arterial blood gas measurement or pulse oximetry, this is probably an overestimate, with evidence that levels of 2.0 g/dL of deoxyhemoglobin may reliably produce cyanosis. Since, however, the presence of cyanosis is dependent upon there being an absolute quantity of deoxyhemoglobin, the bluish color is more readily apparent in those with high hemoglobin counts than it is with those with anemia. Also, the bluer the color, the more difficult it is to detect on deeply pigmented skin. When signs of cyanosis first appear, such as on the lips or fingers, intervention should be made within 3–5 minutes because a severe hypoxia or severe circulatory failure may have induced the cyanosis.
The name "cyanosis" literally means "the blue disease" or "the blue condition". It is derived from the color cyan, which comes from κυανός, "kyanós", the Greek word for "blue".