Introduction to Pernicious anemia

Pernicious anemiaPernicious anemia  is a decrease in red blood cells that occurs due to impaired absorption of vitamin B-12 because of a lack of intrinsic factor (IF) in gastric secretions.

It occurs as a relatively common adult form of anemia that is associated with gastric atrophy and a loss of IF production and as a rare congenital autosomal recessive form in which IF production is lacking without gastric atrophy.

By definition, pernicious anemia refers specifically to vitamin B-12 deficiency resulting from a lack of production of IF in the stomach.

Causes

Common causes of pernicious anemia include:

  • Weakened stomach lining (atrophic gastritis)
  • An autoimmune condition in which the body’s immune system attacks intrinsic factor protein or the cells that make it.

Very rarely, pernicious anemia is passed down through families. This is called congenital pernicious anemia. Babies with this type of anemia do not make enough intrinsic factor or cannot properly absorb vitamin 12 in the small intestine.

Pathology

Vitamin B12 cannot be produced by the human body, and must be obtained from the diet. Normally, dietary B12 is absorbed by the body in the small bowel only when it is bound by the intrinsic factor (IF) produced by parietal cells of the gastric mucosa. Pernicious anemia is thought to occur when the body’s immune system mistakenly targets the IF, with a loss of parietal cells. Insufficient IF results in insufficient absorption of the vitamin. Although the normal body stores three to five years’ worth of B12 in the liver, the usually undetected autoimmune activity in one’s gut over a prolonged period of time leads to B12 depletion and the resulting anemia. Inhibition of DNA synthesis in red blood cells results in the formation of large, fragile megaloblastic erythrocytes.

Clinical Presentation

The onset of pernicious anemia usually is insidious and vague. The classic triad of weakness, sore tongue, and paresthesias may be elicited but usually is not the chief symptom complex. Continue reading “Introduction to Pernicious anemia”

Managing Head Injuries

Head injury can be defined as any alteration in mental or physical functioning related to a blow to the head. Loss of consciousness does not need to occur.

Head injury refers to trauma of the head. This may or may not include injury to the brain.

Acute Management

In the setting of acute head injury, give priority to the immediate assessment and stabilization of the airway and circulation.

Following stabilization, direct attention to prevention of secondary injury. Keep mean arterial pressures above 90 mm Hg; arterial saturations should be greater than 90%. Urgent CT scanning is a priority.

Most head injuries are of a benign nature and require no treatment beyond analgesics and close monitoring for potential complications such as intracranial bleeding. If the brain has been severely damaged by trauma, neurosurgical evaluation may be useful.

Monitoring Intracranial Pressure

Since elevated intracranial pressure is an independent predictor of poor outcome. If the intracranial pressure rises above 20-25 mm Hg, intravenous mannitol, CSF drainage, and hyperventilation can be used. Hypertonic saline has also been used in lieu of mannitol to lower intracranial pressure.

Nutritional support

Head injury induces a hypermetabolic state and early nutritional interventions may be as critical as cerebral perfusion pressure. Parental or enteral feedings reduced mortality by at least 50% in one study when given early in the course of severe head injury.

Advice on discharge

Patients who are discharged after mild head injury should be given an instruction sheet for head injury care. The sheet should explain that the person with the head injury should be awakened every 2 hours and assessed neurologically. Caregivers should be instructed to seek medical attention if patients develop severe headaches, persistent nausea and vomiting, seizures, confusion or unusual behavior, or watery discharge from either the nose or the ear. Continue reading “Managing Head Injuries”

Plantar Heel Pain

Plantar heel pain is a commonly encountered orthopedic problem that can cause significant discomfort and a limp because of the difficulty in bearing weight. The etiologies of this condition are multiple; therefore, a careful clinical evaluation is necessary for its appropriate management. Nonsurgical or conservative care is successful in most cases.

Pathology

The specialized soft tissue at the heel functions as a shock absorber. The subcutaneous structure consists of fibrous lamellae arranged in a complex whorl containing adipose tissues that attach with vertical fibers to the dermis and the plantar aponeurosis.

An inflammatory response and reparative process can double the thickness of the plantar fascia, which is normally approximately 3 mm. Biopsy specimens reveal collagen necrosis, angiofibroblastic hyperplasia, chondroid metaplasia, and calcification.

The heel pain can also have a neurologic basis. The tibial nerve, with nerve roots from L4-5 and S2-4, courses in the medial aspect of the hindfoot, through the tarsal tunnel, under the flexor retinaculum, and over the medial surface of the calcaneus. The calcaneal branch, arising directly from the tibial nerve, carries sensation from the medial and plantar heel dermis. The tibial nerve and its branches in the hindfoot can be involved with compressive neuropathies. A valgus heel can stretch in the tibial nerve.

Clinical Presentation

A careful history and physical examination is valuable in identifying the etiology of heel pain. Taking a comprehensive medical and general history is important in order to distinguish between various causes.

  • The most common cause of plantar heel pain in both athletic and nonathletic populations is proximal plantar fasciitis.
  • The discomfort commonly manifests spontaneously and insidiously without an antecedent trauma or fever. Occasionally, some patients state they might have stepped on a small object such as a pebble or they may have recently started an exercise regimen involving walking or running.
  • The pain is localized to the plantar and medial aspects of the heel. It is worse typically with the first few steps in the morning. The pain causes patients to limp for approximately half an hour. It is also worse after a period of rest, such as after standing up from a chair or getting out of a car.
  • An acute onset of pain, especially after a vigorous or sudden athletic activity, can be indicative of traumatic rupture of the plantar fascia.
  • Fat pad atrophy in elderly patients and in persons who have received multiple steroid injections manifests with pain under the heel that is more diffuse, involving most of the weight-bearing surface.
  • Pain radiating from the heel distally or proximally and associated with numbness, paresthesia, or a burning sensation after activity and continuing even after rest is likely to be neurologic in origin.
  • Significant loss of appetite and weight or pain at night can be indicative of a neoplasm.

Examination

A general examination is necessary to rule out systemic causes of heel pain. A spine examination is required if the pain radiates. Continue reading “Plantar Heel Pain”

Parkinson’s Disease

Parkinson disease is recognized as one of the most common neurologic disorders, affecting approximately 1% of individuals older than 60 years.

Parkinson’s disease (also known as Parkinson diseaseParkinson’sidiopathic parkinsonismprimary parkinsonismPD, or paralysis agitans) is a degenerative disorder of the central nervous system. The motor symptoms of Parkinson’s disease result from the death of dopamine generating cells in the substantia nigra, a region of the midbrain.

The classic motor features of Parkinson disease typically start insidiously and emerge slowly over weeks or months, with tremor being the most common initial symptom. The 3 cardinal signs of Parkinson disease are resting tremor, rigidity, and bradykinesia.

Pathology

No specific, standard criteria exist for the neuropathologic diagnosis of Parkinson disease, as the specificity and sensitivity of its characteristic findings have not been clearly established. However, the following are the 2 major neuropathologic findings in Parkinson disease:

  • Loss of pigmented dopaminergic neurons of the substantia nigra pars compacta
  • The presence of Lewy bodies and Lewy neurites

The loss of dopamine neurons occurs most prominently in the ventral lateral substantia nigra. Approximately 60-80% of dopaminergic neurons are lost before the motor signs of Parkinson disease emerge.

Causes

Most people with Parkinson’s disease have idiopathic Parkinson’s disease (having no specific known cause). A small proportion of cases, however, can be attributed to known genetic factors. Other factors have been associated with the risk of developing PD, but no causal relationship has been proven.

Epidemiology

The incidence and prevalence of Parkinson disease increase with age, and the average age of onset is approximately 60 years. Onset in persons younger than 40 years is relatively uncommon. Parkinson disease is about 1.5 times more common in men than in women.

Clinical Presentation

Onset of motor signs in Parkinson disease is typically asymmetric, with the most common initial finding being an asymmetric resting tremor in an upper extremity. Over time, patients notice symptoms related to progressive bradykinesia, rigidity, and gait difficulty. The first affected arm may not swing fully when walking, and the foot on the same side may scrape the floor. Over time, axial posture becomes progressively flexed and strides become shorter.

Initial clinical symptoms in Parkinson disease include the following: Continue reading “Parkinson’s Disease”

Bipolar Affective Disorder

Bipolar disorder or bipolar affective disorder, historically known as manic-depressive disorder, is a psychiatric diagnosis that describes a category of mood disorders defined by the presence of one or more episodes of abnormally elevated energy levels, cognition, and mood with or without one or more depressive episodes.

Bipolar disorder, or manic-depressive illness (MDI), is one of the most common, severe, and persistent mental illnesses. Bipolar disorder is a serious lifelong struggle and challenge. It is also useful to note that other mental health disorders and general medical conditions are more prevalent in patients with bipolar disorders.

Bipolar disorder is characterized by periods of deep, prolonged, and profound depression that alternate with periods of an excessively elevated or irritable mood known as mania. The symptoms of mania include a decreased need for sleep, pressured speech, increased libido, reckless behavior without regard for consequences, grandiosity, and severe thought disturbances, which may or may not include psychosis. Between these highs and lows, patients usually experience periods of higher functionality and can lead a productive life.

Etiology

A number of factors contribute to bipolar disorder, including genetic, biochemical, psychodynamic, and environmental factors. Genetic factors contribute substantially to the likelihood of developing bipolar disorder, and environmental factors are also implicated.

First-degree relatives of people with BPI are approximately 7 times more likely to develop BPI than the general population.

Multiple biochemical pathways likely contribute to bipolar disorder, which is why detecting one particular abnormality is difficult.

In some instances, the cycle may be directly linked to external stresses or the external pressures may serve to exacerbate some underlying genetic or biochemical predisposition.

Pregnancy is a particular stress for women with a manic-depressive illness history and increases the possibility of postpartum psychosis.

Clinical Signs and Symptoms

Bipolar disorder is a condition in which people experience intermittent abnormally elevated (manic or hypomanic) and, in many cases, abnormally depressed states for periods of time in a way that interferes with functioning. Not everyone’s symptoms are the same, and there is no simple physiological test to confirm the disorder. Bipolar disorder can appear to be unipolar depression. Diagnosing bipolar disorder is often difficult, even for mental health professionals. What distinguishes bipolar disorder from unipolar depression is that the affected person experiences states of mania and depression. Often bipolar is inconsistent among patients because some people feel depressed more often than not and experience little mania whereas others experience predominantly manic symptoms. Additionally, the younger the age of onset—bipolar disorder starts in childhood or early adulthood in most patients—the more likely the first few episodes are to be depression. Because a bipolar diagnosis requires a manic or hypomanic episode, many patients are initially diagnosed and treated as having major depression.

Manic Episodes

Manic episodes are characterized by at least 1 week of profound mood disturbance, characterized by elation, irritability, or expansiveness (referred to as gateway criteria). Continue reading “Bipolar Affective Disorder”

Introduction to Diabetic Foot

diabetic-foot-Foot infections are the most common problems in persons with diabetes. These individuals are predisposed to foot infections because of a compromised vascular supply secondary to diabetes.

diabetic foot is a foot that exhibits any pathology that results directly from diabetes mellitus or any long-term (or “chronic”) complications of diabetes mellitus. Presence of several characteristic diabetic foot pathologies is called diabetic foot syndrome.

Infections in patients with diabetes are difficult to treat because these individuals have impaired microvascular circulation, which limits the access of phagocytic cells to the infected area and results in a poor concentration of antibiotics in the infected tissues.

Etiology

Diabetes mellitus is a disorder that primarily affects the microvascular circulation. In the extremities, microvascular disease due to “sugar-coated capillaries” limits the blood supply to the superficial and deep structures. Pressure due to ill-fitting shoes or trauma further compromises the local blood supply at the microvascular level, predisposing the patient to infection, which may involve the skin, soft tissues, bone, or all of these combined.

Diabetes also accelerates macrovascular disease, which is evident clinically as accelerating atherosclerosis and/or peripheral vascular disease. Most diabetic foot infections occur in the setting of good dorsalis pedis pulses; this finding indicates that the primary problem in diabetic foot infections is microvascular compromise.

Risk factors

Two main risk factors that cause diabetic foot ulcer are Diabetic Neuropathy and micro as well as macro ischemia. Diabetic patients often suffer from diabetic neuropathy due to several metabolic and neurovascular factors. Type of neuropathy called peripheral neuropathy causes loss of pain or feeling in the toes, feet, legs and arms due to distal nerve damage and low blood flow. Blisters and sores appear on numb areas of the feet and legs such as metatarso-phalangeal joints, heel region and as a result pressure or injury goes unnoticed and eventually become portal of entry for bacteria and infection.

Microbial Organisms involved in Infection

The microbiologic features of diabetic foot infections vary according to the tissue infected. In patients with diabetes, superficial skin infections, such as cellulitis, are caused by the same organisms as those in healthy hosts, namely group A streptococci and Staphylococcus aureus.

Deep soft-tissue infections in diabetic persons can be associated with gas-producing, gram-negative bacilli.

Acute osteomyelitis usually occurs as a result of foot trauma in an individual with diabetes. The distribution of organisms is the same as that in an individual without diabetes Continue reading “Introduction to Diabetic Foot”

Pemphigus Vulgaris A Dermatological Condition

Introduction

Pemphigus is derived from the Greek word pemphix meaning bubble or blister.

The term pemphigus refers to a group of autoimmune blistering diseases of the skin and mucous membranes characterized histologically by intraepidermal blister and immunopathologically by the finding of in vivo bound and circulating immunoglobulin G (IgG) antibody directed against the cell surface of keratinocytes.

Pathophysiology

Pemphigus vulgaris is an autoimmune, intraepithelial, blistering disease affecting the skin and mucous membranes and is mediated by circulating autoantibodies directed against keratinocyte cell surfaces.

Blisters in pemphigus vulgaris are associated with the binding of IgG autoantibodies to keratinocyte cell surface molecules. These intercellular or pemphigus vulgaris antibodies bind to keratinocyte desmosomes and to desmosome-free areas of the keratinocyte cell membrane. The binding of autoantibodies results in a loss of cell-to-cell adhesion, a process termed acantholysis. The antibody alone is capable of causing blistering without complement or inflammatory cells.

Incidence

Pemphigus vulgaris has been reported to occur worldwide. Pemphigus vulgaris incidence varies from 0.5-3.2 cases per 100,000 population. Pemphigus vulgaris incidence is increased in patients of Ashkenazi Jewish descent and those of Mediterranean origin. Few familial cases have been reported.

The male-to-female ratio is approximately equal. In adolescence, girls are more likely to be affected than boys.

The mean age of onset is approximately 50-60 years.

Clinical Presentation

Pemphigus vulgaris presents with oral lesions in 50-70% of patients, and almost all patients have mucosal lesions at some point in the course of their disease. Mucosal lesions may be the sole sign for an average of 5 months before skin lesions develop, or they may be the sole manifestation of the disease. The diagnosis of pemphigus vulgaris should Continue reading “Pemphigus Vulgaris A Dermatological Condition”