It transpired that the abnormal skin color had been present since infancy. [acutecaretesting.org]

See Clues on the Skin: Acute Poisonings, a Critical Images slideshow, to help diagnose patients based on their dermatologic presentations. [emedicine.medscape.com]

She had presented at 2 years of age with anemia and splenomegaly, and later the diagnosis of HbE β thalassemia was established. [ashpublications.org]

[…] as a speaker from Astra Zeneca, BMS, and Janssen; AP participated in studies conducted by the Clinical Research Center of the Bordeaux Teaching Hospital and funded by Novartis, Sanofi-Aventis, Lundbeck, and Vivatech, none of which were related to the present [bmj.com]

• Chocolate-Brown Colored Blood

  Case history 2: Chocolate-brown-colored blood suggests methemoglobinemia Blood containing a high concentration of methemoglobin is chocolate brown in color rather than the dark red of deoxygenated (venous) blood or the bright red of oxygenated (arterial [acutecaretesting.org]

• Fatigue

  In rare cases, methemoglobinemia beta-globin type can cause headaches, weakness and fatigue. Symptoms may appear at the age of 6 months. [ivami.com]

  However, in rare cases, severe methemoglobinemia, beta-globin type can cause headaches, weakness, and fatigue. Frequency The incidence of methemoglobinemia, beta-globin type is unknown. [medlineplus.gov]

  Severe methemoglobinemia (>50 %) is associated with increasing breathlessness and fatigue. Confusion, drowsiness and coma ensue; there may be seizures. [acutecaretesting.org]

  Fatigue, flulike symptoms, and headaches may be the only manifestations in the initial phase. [emedicine.medscape.com]

• Anemia

  […] its increased production are required in other types of thalassemia and sickle-cell anemia. [ashpublications.org]

  Symptoms of anemia develop when this percentage increases over 10%, and levels of 70% are generally fatal. Methemoglobin can be increased due to two main causes. [medicinenet.com]

  In patients with severe anemia, a higher percentage of methemoglobin is required for cyanosis to be obvious. These patients are more likely to exhibit signs of hypoxemia and have less cyanosis than is seen in patients who do not have anemia. [emedicine.medscape.com]

  The functional anemia that characterizes methemoglobinemia is due to the combined effect of reduced oxygen-carrying capacity and reduced release of oxygen to the tissues. [acutecaretesting.org]

• Weakness

  In rare cases, methemoglobinemia beta-globin type can cause headaches, weakness and fatigue. Symptoms may appear at the age of 6 months. [ivami.com]

  However, in rare cases, severe methemoglobinemia, beta-globin type can cause headaches, weakness, and fatigue. Frequency The incidence of methemoglobinemia, beta-globin type is unknown. [medlineplus.gov]

  […] associated with higher levels of methemoglobin are as follows: 3-15% - Slight discoloration (eg, pale, gray, blue) of the skin 15-20% - Cyanosis, though patients may be relatively asymptomatic 25-50% - Headache, dyspnea, lightheadedness (even syncope), weakness [emedicine.medscape.com]

• Pallor

  […] physical finding) Cyanosis – This occurs in the presence of 1.5 g/dL of methemoglobin (as compared with 5 g/dL of deoxygenated hemoglobin) Seizures Coma Dysrhythmia (eg, bradyarrhythmia or ventricular dysrhythmia) Acidosis Cardiac or neurologic ischemia Pallor [emedicine.medscape.com]

• Dyspnea

  Symptoms associated with higher levels of methemoglobin are as follows: 3-15% - Slight discoloration (eg, pale, gray, blue) of the skin 15-20% - Cyanosis, though patients may be relatively asymptomatic 25-50% - Headache, dyspnea, lightheadedness (even [emedicine.medscape.com]

• Cyanosis

  This alteration of hemoglobin in the blood gives a brown color and causes cyanosis. Signs and symptoms of methemoglobinemia beta-globin type are generally limited to cyanosis, which does not cause any health problems. [ivami.com]

  The ferric iron cannot bind oxygen and causes cyanosis and the brown appearance of blood. [medlineplus.gov]

  At the 6-month follow-up methemoglobin was 20 %; cyanosis had resolved. [acutecaretesting.org]

  Heterozygotes have 50% enzyme activity and no cyanosis; homozygotes who have elevated methemoglobin levels above 1.5% have clinical cyanosis. [emedicine.medscape.com]

  In most individuals with beta-globin type methemoglobinemia, the only symptom is cyanosis, which is a bluish appearance of the skin, mucous membranes, or the area underneath the fingernails due to a lack of oxygen in the blood. [medicinenet.com]

• Short Arm

  This process is due to mutations in the gene HBB (hemoglobin subunit beta), located on the short arm of chromosome 11 (11p15.5), encoding the protein beta-globin. This protein is a subunit of hemoglobin, which is found inside the erythrocytes. [ivami.com]

• Headache

  In rare cases, methemoglobinemia beta-globin type can cause headaches, weakness and fatigue. Symptoms may appear at the age of 6 months. [ivami.com]

  However, in rare cases, severe methemoglobinemia, beta-globin type can cause headaches, weakness, and fatigue. Frequency The incidence of methemoglobinemia, beta-globin type is unknown. [medlineplus.gov]

  Symptoms of more profound hypoxia, including increased heart rate, headache, dizziness and anxiety, accompany deepening cyanosis as methemoglobin rises above 20 %. [acutecaretesting.org]

  Fatigue, flulike symptoms, and headaches may be the only manifestations in the initial phase. [emedicine.medscape.com]

• Sleep Disturbance

  Sleep disturbance is associated with incident dementia and mortality. Curr Alzheimer Res2013;10:767-75. ↵ Kang JE, Lim MM, Bateman RJ, Lee JJ, Smyth LP, Cirrito JR, et al. Amyloid-beta dynamics are regulated by orexin and the sleep-wake cycle. [bmj.com]

(See Workup.) The most important aspects of the management of methemoglobinemia are recognition of the condition and prompt initiation of treatment, when indicated. [emedicine.medscape.com]

• Erythroblast

  Observations on the relationship between gamma-globin chain content and globin chain precipitation in thalassaemic erythroblasts and on the composition of erythroblastic inclusions in Hb E/beta-thalassaemia., Eur J Haematol, 1997, vol. 59 (pg. 305 - 309 [ashpublications.org]

The most important aspects of the management of methemoglobinemia are recognition of the condition and prompt initiation of treatment, when indicated. For mild asymptomatic cases, treatment is purely for cosmetic or psychological reasons. [emedicine.medscape.com]

As stated in international guidelines, however, treatments should be of short duration and not exceed three months. [bmj.com]

Table 2 Further biochemical and related analyses of the propositus, including, in some cases, data obtained before and after treatment with vitamin C Variable (units), normal range Treatment period Ascorbate (nmol/mL), 28-84 Met Hb (%), 0.1-0.6 P50 (mm [ashpublications.org]

Methemoglobinemia: from diagnosis to treatment. Rev Bras Anestesiol. 2008 Nov-Dec;58(6):651-64. Review. English, Portuguese. Citation on PubMed Melarkode K, Prinzhausen H. [medlineplus.gov]

There is no available treatment to lower the methemoglobin caused by HbM. [acutecaretesting.org]

Prognosis The prognosis of mild cases of methemoglobinemia is very favorable. In severe cases, the prognosis is determined by the degree of anoxic end-organ damage. [emedicine.medscape.com]

Methemoglobinemia: etiology, pharmacology, and clinical management. Ann Emerg Med. 1999 Nov. 34(5):646-56. [Medline]. Forestier A, Pissard S, Cretet J, Mambie A, Pascal L, Cliquennois M, et al. [emedicine.medscape.com]

The epidemiology of long-term benzodiazepine use. Int Rev Psychiatry2005;17:189-97. ↵ Egan M, Moride Y, Wolfson C, Monette J. Long-term continuous use of benzodiazepines by older adults in Quebec: prevalence, incidence and risk factors. [bmj.com]

– Aniline dyes, nitrobenzene, naphthalene (moth balls), aminophenol, and nitroethane (nail polish remover) During the COVID-19 pandemic, cases of acquired methemoglobinemia have been reported in patients treated with hydroxychloroquine. [54, 55, 56] Epidemiology [emedicine.medscape.com]

Biological plausibility The deleterious effects of benzodiazepines on memory are well documented.22 23 No univocal pathophysiological mechanism, however, can be reasonably advanced to explain an increased risk of dementia. [bmj.com]

The presence of anemia and cyanosis despite oxygen treatment results from both of these effects. [5, 6] (See Pathophysiology and Etiology.) Methemoglobinemia occurs when red blood cells (RBCs) contain methemoglobin at levels higher than 1%. [emedicine.medscape.com]

Pathophysiology of beta thalassemia., Disorders of Hemoglobin, 2001 1st Ed Cambridge Cambridge University Press (pg. 233 - 251 ) 34,. [ashpublications.org]

Wounds were treated with mafenide-acetate dressings to prevent infection. [acutecaretesting.org]

Curcumin could prevent methemoglobinemia induced by dapsone in rats. Food Chem Toxicol. 2011 Jul. 49(7):1638-41. [Medline]. Note chocolate brown color of methemoglobinemia. [emedicine.medscape.com]

To prevent plasma protein precipitation, the ferric-reducing ascorbate buffer was diluted 1 in 10 before use. Plasma haptoglobin was measured with the use of a commercial assay (procedure TP.801; Tridelta Development Ltd). [ashpublications.org]

To date, no preventive or curative treatment has been shown to be satisfactorily effective in Alzheimer’s disease. For this reason, the search for putative alterable risk factors should be prioritised. [bmj.com]