Last Post !

This is the final post of this Summer term. It was a pleasure sharing all the information and learning from other students' posts; this truly has been a great learning experience. Even though this semester has been too short and hectic, I really feel like I have added a tremendous amount of information to my knowledge.

These posts have increased my knowledge in the topic area, especially when it comes to thrombocytosis and its different focus areas in children.

I have tried to find new interesting topics that relate to us as future medical technologists, and I hope that you have found my posts useful!

Thank you so much for a great semester, and will see you all in the next one.

Hepatitis B

Hepatitis B is an infection caused by Heptatitis B Virus, and is divided into 2 types:

-       Acute Hepatitis B: newly acquired infections. Symptoms usually appear after 1 to 4 months of infecion. Symptoms usually resolve for most patients after few months, with a small number of patients developping fulminant hepatitis, which a life-threatening form of acute hepatitis.

-       Chronic hepatitis B are patients who symptoms did not resolve completeley, lasting longer than 6 months. Chronic hepatitis B infection is permanent. Chronic hepatitis B infection is more prominent and severe in children.

Transmission: HBV is a blood borne virus, transmitted through blood or mucous. Moreover, it is transmitted from infected pregnant mother to fetus. People at high risk of getting infected with HBV virus include: sexual relationship with an infected person, illicit drug use, needle stick in case of healthcare workers and clinical laboratory workers, newborns for mothers with infection.

HBV virus enters the host cells by binding to an unknown receptor, and being endoctyosed. Chaperones transfer the viral DNA to host nucleus where its DNA is transformed into covalently closed circular DNA from whcih four viral mRNAs are made. Those newly formed mRNA are used to make new copies of the viral genome and capsid core protein and viral DNA polymerase. These then undergo further processing to from virions that are released from the cell for further infection or return to the nucleus to make more copies.

Early symptoms of HBV infection include: fatigue, itching, appetite loss, jaundice, dark urine, clay colored stool and nausea and vomiting and dehydration. Patients experience fulminate HBV infection also experience symptoms associated with hepatic encephalopathy.  

http://www.britishlivertrust.org.uk/data/5/content/6/628/imgs/HBV%20Nat%20Hist.JPG

Thrombocytosis Treatment and Medical Care

Treatment of thrombocytosis should be individualized based on risk factors, which include: cardiovascular risk factors(smoking, hypertension, etc.), thrombocytosis histroy, Platelet count greater than 1.5 million x 109/L.

Hydroxyurea, interferon alfa and anagrelide are drugs among treatment of choice for thrombocytopenia. Low dose aspirin has also shown some benefit during treatment. Moreover, plateletpheresis has shown to be beneficial for a prompt decrease in platelet count is case of emergencies and acute

Lifestyle modifications such as smoking cessation, weight loss and exercise are essetial to patients with primary thrombocytosis. Studies have shown the benefit of hydroxyurea treatment for patients with thrombocytosis in decreasing the platelet count; moreover, a clinical trial has shown the overall benefit of taking hydroxyurea and aspirin over anagrelide and aspiring combination, as far as thrombocytosis treatment and less experienced side effects and risk for the patient. Another clinicla control trial has shown that low-dose aspirin by itself may be beneficial in treatment of low-risk patients. 

http://bloodjournal.hematologylibrary.org/content/117/5/1472.full

Link Between Air Pollution and Decreased Immunity Against Mycobacterium Tubeculosis

The alveolar macrophages play a major role in protecting the host against airborne pathogens. However, environmental health scientist showed a major concern on the ability of the environment chemicals to affect the immunological function of these cells.

A recent research has confirmed the existence of a relation between air pollution and decreased immunity against Mycobacterium tubeculosis. The exposure of human to diesel exhaust particles inhibit phagocytic cells. The research was conducted performing experiments that study the ability of phagocytic cells to fight TB in the presence or absence of DEP. After comparing the results, the researchers were able to prove that cells of the immune system become desensitized and less able to fight TB after exposure to air pollution.

The inhibition of the immune system can be exlpained by dysregulation of chemokine and cytokine production, the inability of phagocytic cell to migrate, and the loss of the phagocytosis potential. The effect of air pollution does not only leave the host vulnerable to TB infection but also lead to modifications in other macrophages mechanisms that are essential for pathogen clrearance.

Current statistics state that TB affect ten million people worldwide and cause the death of 1.5 million people per year. The prevalence of the disease is especially high in developing countries that are experiencing sudden industrial growth associated with a increase in air pollution. In addition, a study have shown that by 20 years from now 50% of the population will be moving to urban environment. All this is an indication that TB will keep on affecting a higher number of the population worldwide.

http://www.public.asu.edu/~shaydel/research_001tb_2.html

Laboratories Testing for Differentiating Primary from Secondary Thrombocytosis in a Pediatric Patient

When a pediatric patient presents with thrombocytosis, laboratory studies are performed to be able to determine whether it is a condition of primary thrombocytosis or secondary thrombocytosis. No additional studies need to be performed when physicians strongly suspect  primary thrombocytosis . However, several lab testing can help  differentiate secondary from primary thrombocytosis.  Fibrinogen level, acute phase reactants, C-reactive protein, von Willebrand factor and factor VIII are found to be remarkably elevated in pediatric patients with secondary thrombocytosis but normal in case of primary thrombocytosis. In the beginning of reactive thrombocytosis, serum TPO levels can be elevated; But with the progression of the disease TPO can return to normal values. Therefore, it is very important to carefully interpret TPO serum values in a timely manner. Whereas in case of primary thrombocytosis induced by  a mutation in 5’ UTR (5’ untranslated region), which  play a role in inhibition of TPO mRNA,  elevated value of TPO would be present all the time. Nevertheless, essential thrombocytosis due to other mutation can have normal TPO levels.  The most common mutation in essential thrombocytosis is JAK2 mutation, thus when essential thrombocytosis is suspected we always test for JAK2 mutation.

                                           http://spittoon.23andme.com/wp-content/uploads/2012/03/MPN-progression.png

This is an algorithm that presents suggested work-up for platelet count that are over 1 million/μL:

                                                         http://emedicine.medscape.com/article/959378-workup

Patient Guidelines for Antibiotics Use

Antibiotic resistance has a great impact on increased morbidity and mortality in patients with infections due to resistant organisms. It is important for us as healthcare professionals to increase the awareness of drug resistance for the general public, and its great influence on our societies and quality of life in the long run. Overuse and misuse of antibiotic administration is the primary cause of antibiotic resistance.  Moreover, antibiotic misuse even in other fields such as agricultural field will contribute significantly to antibiotic resistance in humans.

Therefore, Antibiotic resistance can only be managed through proper use and administration of antibiotics.

                                          http://scienceinthetriangle.org/wp-content/uploads/2011/02/antibiotic-resistance-graph1.jpg

This is a guideline, intended for patients, that provides guidance on the appropriate use of antibiotics:

-       Proper education of the patient for antibiotic use is vital. Patients should be taught to not expect antibiotics for every ailment. Physicians should perform thorough investigation of illness and determine the best course of therapy.

-       Ask your health practitioner or pharmacist for specific information on how to use the antibiotics. Also, read and understand the drug information provided by the pharmacist.

-       Always finish the therapy by taking the entire course of antibiotics, even when symptoms become better.

-       Follow proper schedules for antibiotics.

-       Determine if the antibiotic needs to be taken with food or not. Food intake might affect the absorption of certain drugs and improper food intake can lead to sub-therapeutic levels of certain antibiotics.

-       Do not take any antibiotics if not prescribed to you by a licensed health practitioner.

The Utility of Platelet Count as a Potential Predictor of Infant Bacterial Infection

 

The evaluation of an infant with febrile illness and no obvious focus of infection is one of the main challenging job that faces pediatricians. The general condition of the infant can generally be deceptive, and is labeled Serious Bacterial Infection (SBI). Laboratory markers that have been used to predict SBI include raised white blood cell (WBC) counts, C-reactive protein, pro-calcitonin and even interleukin-6 levels. White blood cell count by itself, does not compare well with relatively more recent markers such as C-reactive protein and pro-calcitonin.

A new study revises the relationship between reactive thrombocytosis among febrile infants and assesses the utility of platelet count as a potential predictor of serious bacterial infection in these patients.

The mean platelet count in SBI infants was observed to be significantly higher than non-SBI infants. Infections of the respiratory, urinary and gastrointestinal tracts, as well as bones and meninges were the most common causes of reactive thrombocytosis.  A platelet count of > 45,000/mL in addition to other laboratory data such as WBC> 15,000 mL and CRP ≥2mg/dL was a strong indicator of SBI.

The study asserts the addition of a routine hematology parameter like platelet count to the sepsis screen results in better differentiating between SBI and non-SBI infants, which delineates the severity of the infection and the extent of the treatment. This finding might be useful in the ER  and in pediatrics where quick turnaround time is necessary. 

                                                         http://physiologyonline.physiology.org/content/17/1/6/F3.large.jpg

Lenses Associated Infection And Its Prevention.

 

                                        http://www.medicalook.com/Eye_diseases/Keratitis.html

Bacterial keratitis is the infection of the eye cornea.  It is one of the potential complications of contact lens use and refractive corneal surgery. This infection is caused by Interruption of the corneal epithelium or abnormal tear film. It is usually caused by the virulence factors that destroy the cornea. Initially, the epithelium and stroma undergo necrosis then neutrophils surround exacerbate the injury and cause necrosis of the stromal lamellae. Cytokines elicits an outpouring of inflammatory cells, which might cause a hypopyon (pus in eye). Bacterial toxins and elastase and alkaline protease enzymes may be produced, which further contributes to the destruction of the cornea.

The most common bacteria causing bacterial keratitis are: Pseudomonas aerugionsa, and Staphylococcus species, others such as Enterobacteriaceae (Klebsiella, Enterobacter, Serratia, and Proteus) as well as Streptococcus. Moreover, up to 20% of fungal keratitis cases are complicated by bacterial co-infection.

The FDA has the following recommendations to help the prevention of bacterial keratitis:

• Stop using any eye cosmetic that causes irritation immediately.
• Avoid using eye cosmetics if you have an eye infection or the skin around the eye is inflamed. Wait until the area is healed. Discard any eye cosmetics you were using when you got the infection.
• Wash your hands before applying eye cosmetics.
• Make sure that any instrument you place in the eye area is clean.
• Don't share your cosmetics.
• Don't allow cosmetics to become covered with dust or contaminated with dirt or soil.
• Don't use old containers of eye cosmetics.
• Discard dried-up mascara.
• Don't store cosmetics at temperatures above 85 ^oF.
• Never apply or remove eye cosmetics in a moving vehicle.
• Only use cosmetics intended for the eye in the eye area.

In conclusion, early diagnosis and treatment of keratitis will help minimize the chance of any further complications.  Keratitis is serious infection; Successful outcome is warranted through close follow-up, attention to laboratory data, and changing antimicrobial treatment if no clinical improvement.

Pediatric Drug Induced Thrombocytosis

Essential thrombocytosis is very rare in neonates, and most cases of high platelet counts in pediatric patients are due to secondary thrombocytosis. One of the main causes of secondary thrombocytosis in neonates is maternal narcotic drug abuse during pregnancy. Nonetheless, The impact and management of neonatal thrombocytosis are not very well studied yet.

Below are examples of 2 cases that are related to secondary thrombocytosis:

Case 1: A schizophrenic mother who was treated with non-narcotic psychotropic drugs during pregnancy gave birth to a baby suffering from severe prolonged thrombocytosis. Laboratory data revealed platelet count value of 1310 × 10⁹/l on day 15 of his life, and the patient was treated with dipyridamole. His platelet count returned to normal after several months. A bone marrow aspirate was performed to evaluate his disease state. The patient had an increased level of megakaryocytes and normal myeloid and erythroid precursors. In addition, Plasma concentrations of interleukin 6 and thrombopoietin were suppressed. The patient didn’t show any sign of complication from thrombocytosis. 

                                 Figure 1: Plasma platelet counts, thrombopoietin, and interleukin 6 (IL6) concentrations of the patient

                                                          http://fn.bmj.com/content/84/3/F198/F1.large.jpg

Case 2: A 14 days old neonate diagnosed with withdrawal syndrome was admitted to the intensive care unit. He presented very high platelet value of 1168 × 10⁹/l  in the first day of admission, which gradually decreased to 739 × 10⁹/l in a period of 28 days. Upon history investigation, the mother admitted that she was a heroin addict and used methadone during pregnancy.

These cases indicate that thrombocytosis may occur in infants born to mothers treated with non-narcotic psycho-pharmaceutical drugs during pregnancy, as well as mothers who are taking narcotics during pregnancy, and caution is to be considered during treatment of pregnant females. In most similar cases, thrombocytosis goes away in the babies with no severe complications, unless in the presence of bone marrow anomaly.

Watch out how you handle your food!

 

During our busy lives, many times we do not think about foodborne diseases and infections. We might be rushing to serve our burgers to our guests, and forget to properly cook the hamburgers, or we might not be thinking it is a big deal if we re-use the meat fork to grab few fruits on the way. I am attempting to show, through this post, how dangerous foodborne infections with Campylobacter jejuni can be, and the importance of proper food handling and sanitation, and how it is always best to take that extra 5 minutes to properly cook poultry, and any other kind of meat.

There are a wide range of organisms that are associated with foodborne infections, such as Shigella, Salmonella, and E. coli. Campylobacter jejuni, which lives in the intestines, is also one of the most common organisms causing these infections. It is most contracted through ingestion of undercooked poultry or can be contracted through cross-contamination. Short-term diarrhea is the most common symptom of infection with Campylobacter jejuni and mot often resolves on its own in two to ten days or with antibiotic treatment.

Diarrhea and dehydration are the most common consequences of infection with Campylobacter jejuni. However, chronic conditions associated with infection with C. jejuni include Guillain-Barré syndrome (GBS). GBS is an autoimmune disorder in which the patient’s immune system attacks the peripheral nervous system. GBS is the most common cause of acute neuromuscular paralysis in the world. One of the more popular theories is that part of a molecule on the surface of C. jejuni is similar to those found on nerve cells, which leads to the antibody attacking the axons even after the eradication of C. jejuni.

This post delineates the importance of use of safe food protocol while handling poultry and meat, as well as the importance of proper preparation of meat. 

                                                   http://wwwnc.cdc.gov/eid/article/18/2/11-1126-f1.htm

Secondary thrombocytosis

    Secondary thrombocytosis, or reactive thrombocytosis, occurs as a result of a physiologic reaction to a primary event. Primary thrombocytosis in pediatric patients is very rare, while reactive thrombocytosis is very common. It is associated with a diversity of clinical conditions, such as infection or malignant disease. Infections of the central nervous system are the most common cause of an elevated platelet count in children. In addition, several studies have shown that pediatric patients with lower respiratory tract infections often present with thrombocytosis. In these cases, platelet count can be used as a valuable clinical marker to assess the severity of the infection. Malignant diseases are scarcely associated with extreme cases of thrombocytosis.
     The degree of reactive thrombocytosis is related to the child’s age, and increase in platelet count is proportional to hospitalization duration. The degree of thrombocytosis is negatively related to hemoglobin value and positively related to white cell count.
      Usually when the patient is treated and the condition that is stimulating thrombocytosis has ceased, platelet count returns to normal level. Even though the platelet count is highly elevated, complications associated with it are very rare. Physicians should concentrate on the underlying cause of reactive thrombocytosis.

Rhinoscleroma

I found this disease state to be intriguing, therefore I wanted to discuss it in this post, and learn a new topic for this week.  

            Rhinoscleroma (or Scelroma) is a chronic granulomatous bacterial disease of the nose that infects the upper respiratory tract. In rare cases, it can also affect the nasopharynx, larynx, trachea, and bronchi. Scleroma is a tropical disease and is mostly endemic to Africa and Central America, and it slightly affects more females than males.

Scelroma is caused by Klebsiella rhinoscleromatis, which is a subspecie of Klebsiella pneumoniae. Rhinoscleroma is a member of the Enterobacteriaceae family; it is an encapsulated gram-negative, nonmotile, diplobacillus that is sometimes referred to as the "Frisch bacillus," named for Anton von Frisch who has identified the organism. It is contracted directly by droplets or by contamination of food/objects that are subsequently inhaled.

The presentation is often nonspecific and is often unrecognized due to its resemblence for cold symptoms. It should be taken into consideration in cases of chronic rhinitis, even in developed countries. Nasal obstruction is the main complain, and the disease can be divided into 3 stages: catarrhal/atrophic, granulomatous, and sclerotic stages; only the granulomatous stage has diagnostic changes. Cellular immunity is impaired in patients infected with rhinoscleroma but the humoral immunity is preserved. CD4–CD8 ratio within the lesion is altered, showing decreased CD4 lymphocytes and increased CD8 lymphocytes, with a diminished T-cell response. A positive culture in MacConkey agar is diagnostic of rhinoscleroma, but cultures are positive in only 50% to 60% of cases.
Treatment should include long-term antimicrobial for 2 to 3 months with tetracycline being the drug of choice, and surgical intervention in patients with symptoms of obstruction. 

                                                                                     http://www.artandmedicine.com/biblio/authors/Wolkowitsch.html

IMMUNOCOMPROMISED: NO higher risk for UTI!

This week we have discussed urinary tract infection and the different bacteria involved. And I would love to discuss with you the risk of UTI in immunocompromised patients.

In contrary to common believe that immunocompromised patients are at higher risk for urinary tract infection, several studies have shown that the defect in humoral or cellular immunity in immunocompromised patients do not seem to predispose to higher risk for UTI but it affects the clinical symptoms, severity, microbiology, and complications of the infection once the patient has a urinary tract infection.

The frequency of urinary tract infections in immunosuppressed patients other than diabetics or renal transplant recipients is not superior to the frequency of urinary tract infections in non-immunosuppressed patients. The higher incidence of infection seen in renal transplant patients is more related to the period of invasive bladder catheterization rather than to the patient immunocompromised condition.

Because of Neutropenia, urinary tract infection predisposes the patient to bacteremia. Thus, broad-spectrum antibiotics have to be used, which leads to modifications in normal flora, further promoting urinary tract infections with resistant nosocomial pathogens, and can also predispose to fungal infection in the urinary tract.

In urinary tract infection, a functionally and anatomically intact urinary tract and kidney are the main host defenses, with immune mechanisms and phagocytic function playing an important role to LIMIT THE CONSEQUENCES of those infections.

 Diagnostic approach to UTI:

                                           http://www.aafp.org/afp/1999/0301/p1225.html

Primary Thrombocytosis in Babies

I would like to introduce my graduate project “Thrombocytosis in babies” by giving a definition of thrombocytosis and explaining primary thrombocytosis. And then, in later posts I will be focusing more on causes, clinical presentation, pathophysiology, and diagnosis of thrombocytosis in children and babies.

Thrombocytosis in babies

Platelet counts physiologic reference range is 150-400 X 10⁹/L. Thrombocytosis is when platelet count exceed the upper limit. It can be primary or secondary.

 

This is a blood smear of a patient with thrombocytosis: 

                            http://www.thailabonline.com/blood/thrombocytosis1.jpg

Primary thrombocytosis:

There are 2 types of primary thrombocytosis or essential thrombocytosis. Classical primary thrombocytosis is the first type. It is caused by continuous production of platelets, which in this case is not regulated by the physiologic negative feedback mechanism that usually maintains platelet count within the reference range. It can be due to a myeloproliferative disorder such as polycythemia vera, essential thrombocythemia, chronic myelocytic, myelofibrosis with myeloid metaplasia or, very rarely, it can be due to an acute myelocytic leukemia. These patients represent a monoclonal hematopoiesis. Endogenous erythroid colony growth is the main characteristic of their hematopoiesis, with an increase in the expression of granulocyte polycythemia rubra vera-1 (PRV-1) RNA, and is associated by JAK2^V617Fmutation in nearly 30% of the pediatric cases.

However, the second type of primary thrombocytosis is classified as familial thrombocytosis and is due to a mutation of either thrombopoietin receptor gene (mpl) or thrombopoietin (TPO) gene.  Hematopoiesis in familial thrombocytosis is polyclonal.

Welcome To Reina's Bug Blog!!

First of all I want to welcome everyone to Reina’s bug blog. 

I am very excited about this new learning experience. This is a place where we can all share interesting facts, articles, pictures and videos related to the infectious disease class.  In addition, I will be posting information related to my graduate project “thrombocytosis in babies”. Hope my blog will be very informative and useful. Please feel free to leave any comments!  Enjoy :-)