Methemoglobinemia Treatment - Methemoglobinemia diagnosis & test

What is methemoglobinemia? > Bluish skin discoloration > Methemoglobinemia causes

In mild cases of acquired methemoglobinemia, treatment may not be necessary. In fact mild methemoglobinemia may go unnoticed and undiagnosed.

Avoiding and withdrawing the causative food, chemical or drug itself will solve the problem.
Persons having inherited methemoglobinemia type 1 or hemoglobin M disease may be able to carry on their normal lives.
However individuals with hereditary type IIb5 cytochrome reductase deficiency have shortened life expectancy due to severe multiple physiological complications.

In persons with fair skin complexion, the diagnosis is easier requiring fewer tests as the bluish skin discoloration is apparent.
However in individuals with dark skin complexion and hyperpigmentation blemishes symptoms have to be studied and elaborate tests may be necessary for diagnosis and treatment.
Cyanosis and low O₂ saturation reading around 90% may indicate methemoglobinemia.
The diagnosis of methemoglobinemia can be confirmed by test with multiple wavelength co-oximeter or multi-wave length pulse oximeter to directly measure methemoglobin.

Methylene blue in methemoglobinemia treatment

Methylene blue (methylthioninium chloride or C₁₆H₁₈N₃SCl) is used in the treatment in severe cases of Methemoglobinemia.
Methylene blue 1% solution (10 mg/ml) 1 to 2 mg/kg is usually administered by the intravenous route.
This has to be done slowly for about five minutes followed by intravenous flush with saline. The IV administration of methylene blue may be repeated if necessary.
Oxygen supplementation is also done simultaneously.
Methylene blue functions as electron acceptor and makes the methemoglobin reductase enzyme to perform at five times the normal levels.
However in patients with the G6PD (Glucose-6-phosphate dehydrogenase) deficiency, an X-linked recessive hereditary disease, methylene blue is contraindicated.
In  G6PD patients it is very dangerous to use methylene blue as it can lead to severe hemolysis.
Methylene blue, being a potent oxidant, can actually cause methemoglobinemia when administered at levels greater than 7mg/kg.

Ascorbic acid in methemoglobinemia treatment

Vitamin C, being a potent antioxidant, reduces the level of methemoglobin in the blood.
Oral administration vitamin C at 500mg/d may be done on an ongoing basis when methemoglobin levels rise to more than 30%.
Oral methylene blue at about 200-300mg/d or riboflavin at 20mg/d also can be used instead of vitamin C.

Exchange transfusions and hyperbaric oxygen treatment

In severe life-threatening situations exchange transfusions are resorted to save the life of the patient.
In G6PD patients and in individuals in whom there is lack of sufficient progress with methylene blue treatment, exchange transfusion becomes necessary to save the life.
In exchange transfusion, basically, abnormal hemoglobin in RBC is replaced with normal hemoglobin.
In hyperbaric oxygen treatment, by use of plasma dissolved oxygen, tissue oxygenation is achieved.

In infant metabolic acidosis, methemoglobinemia resolution lies in reversal of acidosis with intravenous hydration and bicarbonates.

Methemoglobinemia treatment must done by a qualified professional preferably in a clinic or hospital.

Related topics:
What is methemoglobinemia?
Causes and symptoms

Current topic: Methemoglobinemia treatment

• Home
• Index

Idiopathic guttate hypomelanosis - white spots - causes - symptoms - diagnosis

Home > White spots on skin, lips, fingernails, teeth, tonsils and genitalia > Idiopathic guttate hypomelanosis > Treatment > Causes - symptoms - diagnosis

The causes for Idiopathic guttate hypomelanosis are not exactly known but for its treatment and cure, differential diagnosis has to be done to exclude similar looking disorders.

The exact causes for the appearance of idiopathic guttate hypomelanosis white spots are still under investigation.

Idiopathic guttate hypomelanosis causes

As these white spots appear on the exposed parts of the body it presumed that the exposure to sunlight could be the cause for their appearance.
Idiopathic guttate hypomelanosis appear on most exposed parts of the body like the shin, forearms, shoulders and neck indicating that sun exposure as the likely cause of their appearance.
These white spots appear in the late twenties in some cases but their prevalence is from the early thirties onwards; the concurrent reason could be due the aging process.
In young children and adolescents these white spots are very rarely seen; another indication that the aging process and sun exposure are the main causes.
One of the reason is being light-skinned as these hypomelanosis lesions are rarely seen in darker skinned individuals.
Idiopathic guttate hypomelanosis causes white spots in more number of women than men in the thirties and later on both the genders get equally affected.
In some cases the disorder seem to run in families genetic tendency and inheritance seemed to be one of the causes for these white spots.

Idiopathic guttate hypomelanosis symptoms

• The macules are small in size usually between 2 to 5 mm; one of the important symptoms.
• In very rare instances size up to 10 mm is encountered.
• The lesions are flat and are discrete, circular, oval or angular in shape.
• They usually affect light-skinned individuals; another important symptom.
• They appear on the sun exposed parts.
• Hypomelanosis macules usually appear first on the legs.

Differential diagnosis of idiopathic guttate hypomelanosis

• The macules first appear on the legs and later on forearms. Diagnosis: excludes flat warts, Pityriasis alba and pityriasis versicolor.
• These white spots are discrete and do not show darker border. The lesions are small in size and in very rare cases may reach a diameter of 10 mm. Diagnosis: excludes vitiligo.
• The lesions do not lose sensitivity. Diagnosis: excludes leprosy lesions.

In rare instances histological studies are required for the diagnosis of idiopathic guttate hypomelanosis white spots.

Pityriasis alba pale/white spots signs symptoms diagnosis

Pityriasis alba > Causes > Diagnosis > Treatment
In the diagnosis of pityriasis alba its signs and symptoms must be analysed to arrive at the differential diagnosis to exclude other conditions and infections.

Signs and symptoms of pityriasis alba

Pityriasis alba is an asymptomatic, self-limiting and benign lesion.

It usually appears on kids of the age 3 -16 years.

The lesions are usually limited to face, especially cheeks, around mouth and chin.

Pityriasis alba may also affect shoulders, neck and arms.

In very rare cases extensive lesions of pityriasis alba may appear all over the body.

Pityriasis alba initially appear like raised red or pink patches sometime with mild itch.

After some time these pityriasis alba patches flatten out and look pale with depigmentation, which is not total.

The spots are oval or round, about 2cm in size and appearing in several numbers.

Pityriasis alba patches have small dry scales which can be seen on closer examination.

The spots appears to worsen during cold dry conditions and flake.

In summer the patches may appear prominent due to tanning of the surrounding areas of normal skin.

These lesions are not contagious and the causative agent is not known.

Pityriasis alba resolves by itself after some time and the patches may take a long time for repigmentation.

Diagnosis of pityriasis alba

Pityriasis alba is diagnosed by taking into account its symptoms and excluding the other skin conditions and diseases by differential diagnosis.

Diagnosis of hypopigmentation to exclude the other diseases

The complete history of dermatitis in the patient is noted with especial attention to the area under investigation. Old skin injuries, marks of dermatitis and infections may show hypopigmentations and take a long time to get normal pigmentation.

The possibility of the affected area being the old hypo pigmented spot of earlier conditions has to be ruled out.

Diagnosis to exclude tinea versicolor and other fungal infections

The possibility of the lesion being due to fungal infections is to be ruled out by conducting Wood's lamp test and KOH test.

Diagnosis to exclude psoriasis

The distribution of the lesions sparing scalp, knees and elbows excludes psoriasis.

Diagnosis to exclude vitiligo

In vitiligo the depigmentation is complete and it is usually a progressive condition. On the face usually the areas around the mouth and eyes are affected and margins are marked. There is no scale formation.

Diagnosis to rule out nummular dermatitis

Nummular dermatitis can be ruled out by its characteristic intense itch.

Nevus depigmentosus is present from birth and is stable.

If the diagnosis is pityriasis alba, relax and follow the skin care efforts given in the treatment post.

• Home
• Index

Diagnosis of tinea (pityriasis) versicolor fungal infections

Malassezia furfur > Tinea versicolor > Causes > Symptoms > Diagnosis > Treatment

Diagnosis of tinea versicolor can be easily done with visual examination and when in doubt can be confirmed by Wood's lamp or by KOH test.

Diagnosis of tinea versicolor by visual observations

An experienced dermatologist can easily do the diagnosis of the presence of tinea versicolor by visual observations. The area of infection, age of the person involved, climatic condition, and the history of earlier infections can guide him to the exact problem. The flat, round or oval lesions with thin dusty scales, growing and merging to form large patches shows the presence of tinea versicolor.

Diagnosis of tinea versicolor by Wood's lamp

Wood's lamp generates UV light and is fitted with Wood's filter alowing only rays of bandwith around 365 nm.to pass through. Though the use of Wood's lamp does not require particular skill attention must be given to following aspects to get correct results and diagnosis. The lamp must be allowed to warm up for one minute.

The examination must be carried out in a dark room. Alternatively a lamp with a hood to cover the area under examination with a peephole to see the affected area can be used. The lamp must be held about 4 - 6 inches from the skin lesion under diagnosis. Washing the affected area before the examination may mislead the diagnosis and should be avoided.

Topical applications on the skin should be wiped off as these may give their own fluorescence and mislead the results. Looking directly at the UV light should be avoided. There is very scant fluorescence from the normal skin whereas Malassezia furfur emits copper orange or yellowish white light. This examination can detect even subclinical tinea versicolor fungal infection and also show the extent of the fungal infection.

Diagnosis of tinea versicolor by KOH test

Alternatively skin scraping may be viewed under microscope to detect the presence of fungus. The superficial skin sample is taken by scraping the affected skin with a scalpel or blade. The collected sample is placed on a slide. The scrapping must be taken from the margin of the lesion.

About 3 drops of 10% KOH (potassium hydroxide) solution is added to the slide. The slide is warmed to dissolve the skin tissue. A drop of lactophenol blue is added and coverslip placed. The sample is examined with a light microscope at high magnification.
Tinea versicolor infection Spaghetti and meatballs appearance of tinea versicolor under microscope
The KOH dissolves the skin tissue leaving behind the fungal cells. The fungal hyphae can be clearly seen. Malassezia furfur can be seen showing the spaghetti and meatballs appearance. Once the diagnosis is completed and the presence of tinea versicolor fungal infection is established the disease can be treated and resolved.

• Home
• Index