Laboratory of Pathology - Staff

Laboratory of Pathology Infection Control Guidelines

Laboratory of Pathology (LP) staff adhere to the NIH Clinical Center (CC) Hospital Epidemiology Service Infection Control Guidelines and NIH CC Bloodborne Pathogens Exposure Control Plan to ensure staff safety and adherence to universal and standard precautions when working with potentially infectious patient material. All LP staff undergo initial and annual safety and infection control training, and are required to use appropriate personal protective equipment (PPE) to prevent skin and mucous membrane exposure when contact with potentially infectious material. These policies and procedures apply to all LP clinical staff who come in contact with human tissues, blood, or potentially infectious materials: staff pathologists, residents and fellows in pathology, medical technologists, cytotechnologists, autopsy assistants, photographers handling human tissues, histology technicians, laboratory visitors and program support staff. 

I. New employees receive training on Universal Precautions and Tuberculosis training in collaboration with the Hospital Epidemiology Service (HES). In addition, all such employees receive instruction on the principles of infection control, with particular emphasis on mycobacterial diseases, and blood and body fluid precautions. All LP staff participates in initial and annual mandatory safety and infection control training (refer to Safety and Environment of Care Responsibilities and Training). Universal precautions and biosafety are covered in the LP Safety Manual that is reviewed annually by all clinical employees of LP.  The Safety Committee monitors compliance of technical personnel and will notify supervisors of delinquencies or problems. The professional staff members (MDs) are monitored through the NIH Clinical Center (CC) Credentials office.

II. Employees receive instruction on the proper use of personal protective equipment in each section, and records are maintained by the section supervisor. 

Training elements include, but is not limited to:

• Use of gloves include ensuring proper fit, replacing gloves when worn or contaminated, not washing or disinfecting gloves, use of hypoallergenic gloves when indicated by patient or health care provider history, and decontamination (washing or sanitizer use) after removal of gloves.
• Use of fluid-resistant gowns or aprons when potential for fluid exposure.
• Use of masks, eye protection and foot cover when appropriate (e.g. autopsy examination).
• Employees requiring use of face masks (e.g. N95 respiratory protection) are fit-tested by OMS and trained in proper use prior to using the PPE.
• Use of head, face/eyes, mask, gown and foot cover during post-mortem examination. Autopsy staff are trained by HES in the use of powered air purifying respirator (PAPR) for use during high-risk aerosol-generating procedures.
• Processing potentially airborne route of transmission specimens n a biological safety hood.

Departmental control measures are reviewed on an annual basis and modifications made as necessary. Structural renovations that may assist in infection prevention and control are instituted.

III. Compliance with Universal Precautions is monitored by individual supervisors. Non-compliance with Universal Precautions is documented as part of annual performance appraisals.

IV. Tuberculosis Surveillance Program (online). Healthcare workers who may be exposed to unfixed human tissues (e.g., grossing surgical specimens, performing autopsies) or those who see patients in the clinics (e.g., assist with FNA) must be enrolled in the NIH Office of Medical Services (OMS) Tuberculosis (TB) Surveillance Program. The LP Clinical  Manager, the OMS Nurse overseeing the Tuberculosis Surveillance Program, and the Epidemiologist on the Hospital Epidemiologist Service coordinate activities and data to ensure appropriate employees are enrolled in the program on an ongoing basis, at least quarterly. New employees must report to OMS when they are hired for their initial physical and receive a PPD skin test if appropriate and are recalled annually for repeat testing. It is the employees' responsibility to follow-up by contacting OMS or by attending one of their walk-in clinics, after they receive their annual notice. If the employee fails to follow-up, the employee is sent a second reminder notice. Through a coordinated effort with OMS and HES, the employees who remain non-compliant or are not enrolled may receive an e-mail from the Clinical Laboratory Manager informing them of the necessity to enroll and become compliant. Any healthcare worker who tests positive for a PPD will receive appropriate counseling and follow-up by OMS, including education on TB symptoms.

V. Creutzfeldt-Jakob Disease (CJD) Special Handling. The NIH Clinical Center's policies for handling pathology specimens of patients with suspected CJD, prion, disease are found in the CC Infection Control guidelines. 

Transmissible Spongiform Encephalopathies (prion diseases): Creutzfeldt-Jakob Disease, Variant Creutzfeldt-Jakob Disease, Fatal Familial Insomnia, Gerstmann-Straussler-Scheinker Syndromem Kuru

Anatomical tissue requires special handling. Neuropathology tissues from suspected cases of Creutzfeldt-Jakob disease should be treated with formic acid. Paraffin blocks and slides prepared from formic-acid-treated tissue may be handled routinely. Formalin and glutaraldehyde-fixed tissue retain infectivity for indefinite periods and should be considered infectious until, or unless, treated with formic acid to reduce infectivity to negligible levels. Specimens must be double-bagged and labeled with a "Special Processing Requirements" sticker (available from the Hospital Epidemiology Service), separated from other surgical, autopsy, and biopsy tissue. Specimens must be hand-delivered and the respective staff notified in advance before the specimens arrive at the Laboratory of Pathology or the Department of Laboratory Medicine.

If tissue has not been treated with formic acid, it must be hand-processed and treated as containing potentially transmissible prions. Double gloves must be worn at all times when handling such tissue. All solutions, including water washes, must be collected and treated with equal volumes of fresh undiluted household bleach for 60 minutes before disposal. Disposables, glassware, tools, etc. must be handled according to the procedures employed in the autopsy room (see Autopsy section below). All scraps of paraffin and unused sections should be collected on a disposable sheet.  No special precautions are needed in handling intact glass slides once they have been coverslipped. Broken slides should be decontaminated and discarded. Paraffin blocks should be stored in a bag or box and labeled as infectious. Alternatively, the laboratory may reseal the cut surface of the blocks with paraffin.

The microtome may be wiped with bleach or NaOH solution. Environmental surfaces in laboratories and procedure areas should be covered with disposable sheets to prevent environmental contamination. Environmental surfaces contaminated with high infectivity tissues should be saturated with undiluted bleach with a contact time of one hour, and then rinsed with water prior to routine cleaning and disinfection with a Clinical Center-approved disinfectant.

VI. Occupational Medical Service provides immunization and surveillance programs to all NIH employees free of charge. Employees are similarly counseled by OMS regarding OSHA requirements for hepatitis B vaccination, and are required to comply with OSHA regulations.

VII. Hand Hygiene

The Clinical Center's Hand Hygiene Policy mandates that all healthcare workers shall practice good hand hygiene to reduce the risk of transmission of organisms to patients, themselves, and coworkers. Careful attention should be given to hand hygiene after removal of gloves, prior to or after patient contact, and especially before touching the eyes or mucosal surfaces. General hand hygiene practices are:

• Indications for hand washing include:

1. Before and after patient contact.
2. Contact with environmental surfaces in the immediate vicinity of patients.
3. After glove removal.
4. Before eating and after using the restroom.

• Techniques for hand hygiene

1. Select the proper amount of hand hygiene solution or agent and wash hands thoroughly.
2. When decontaminating hands with alcohol-based hand rub, apply one full pump depression of the product to palm of hand and rub hands together, covering all surfaces of wrists, hands, fingers, and nails, until hands are dry. This should take 15 to 25 seconds. Follow manufacturer’s recommendations regarding product use.
3. Soap and water are recommended for visibly soiled hands. Wet hands first with warm water, apply product and rub hands vigorously for at least 15 seconds, covering all surfaces of wrists, hands, fingers, and nails. Rinse with water and dry with disposable towel. Use towel to turn off faucet. The use of compatible lotions and creams are recommended to prevent or minimize dryness and irritation. Central Hospital Supply can provide guidance on product selection, if needed.
4. Avoid the use of bar soaps and multiple-use towels.

VIII. Policy on Manipulation of Needles or Sharps

Recapping or manipulating used needles or sharps (scalpels, blades, etc.) is strictly prohibited in the Laboratory of Pathology. The will be no recapping, purposeful bending, breaking, removing from disposable syringes, or other manual manipulations of needles or sharps.

IX. Policy on Eating / Mouth Pipetting / Makeup

The following practices are PROHIBITED in the Laboratory of Pathology: smoking, eating, drinking, application of cosmetics and lip balm, manipulation of contact lenses, and mouth pipetting.

X. Sterilizing Device Monitoring

All surgical instruments used in grossing, autopsy and tissue procurement procedures are cleaned by the Clinical Center Sterile Processing Section. For surgical instruments used for sterile procedures in tissue procurement, LP staff must verify the autoclave tape has been activated to ensure that each instrument was sterilized effectively. The tape will have brown stripes to indicate the sterilization of the instrument was complete. Do not accept any instrument that does not have the tape activated.  

Departmental Procedures

I. Autopsy Service

A. General Policy

During the autopsy, full barrier protection is utilized. The autopsy assistants and medical staff performing the autopsy wear surgical scrub suits, disposable gowns, shoe covers, plastic aprons, and double surgical gloves at all times. Masks, goggles, double gloves, and wrap-around-disposable converters are used in cases of known infection with mycobacteria, Creutzfeldt-Jakob disease (CJD), hepatitis, HIV, or severe viral and bacterial infections. All of these materials are disposed of before leaving the autopsy room. Maintaining sharp instruments and keeping tissues wet minimizes spread of infections. A clean technique is emphasized.

Containers with samples being sent to other departments during the autopsy (microbiological cultures, eyes, etc.) are kept clean. Containers are well constructed with a secure lid to prevent leakage during transport. Autopsy assistants change gloves to handle containers and assist the prosector in obtaining the sample. The sample containers are transported in impervious bags.

• When mycotic or mycobacterial infection is diagnosed at frozen section, the cryostat and microtome blade, as well as all the utensils used during the frozen section procedure, are decontaminated with a 10% sodium hypochlorite solution.
• Unauthorized personnel are denied access to the autopsy area and frozen section room while procedures are in progress.
• For information on blood spills or other potentially infectious material, refer to the Clinical Center Isolation Guidelines. 
• Cleaning of Equipment: All utensils used are soaked in Tergol 800 for a minimum of 30 minutes.* Protective clothing (i.e., shoe covers, aprons, gloves, etc.) will be available on a cart at the door of the autopsy area during all cases.

B. Creutzfeldt-Jakob Disease (CJD)

In addition to the NIH CC Infection Control guidelines for specimen handling for suspected or confirmed CJD cases, post-mortem procedures require additional considerations to ensure staff safety. CJD is one of a group of neurological disorders caused by “unconventional” (“slow” viral) agents (transmissible virus dementia and subacute spongiform encephalopathy are related terms) that are not inactivated by ordinary methods (i.e., formalin fixation). From time to time, such cases may be sent to NIH for autopsy. Somewhat more commonly, a brain biopsy is performed on a patient for whom this diagnosis is a possibility (i.e., atypical dementia, or encephalitic illness). The following are recommendations for the safe handling of tissue:

1. It should be noted that all tissues, body fluids, and blood are considered infectious in this context. However, it must be pointed out that epidemiologic evidence quite clearly shows that the infectivity of the agent is extremely low (i.e., compared to hepatitis B); rare cases of CJD have been reported in neuropathology/histology personnel. (NEJM 318:853-854, 1988). Pathologists should consider taking these special precautions as well in cases of (a) rapidly progressive dementia, (b) dementia with seizures, especially myoclonic seizures, and (c) dementia  associated with cerebellar or lower motor neuron signs. The recommended method for handling these brains to reduce infectivity is immersion of tissue blocks in 95% formic acid. Aerosol formation must be avoided during removal of the brain. If there is any suspicion of Creutzfeldt-Jakob disease, the autopsy should be limited to the brain, and the tissue treated as outlined below. There should be very few exceptions to this rule.
   
   
2. Nursing Instructions:
   • Handling a deceased patient requires the same precautions as if the patient were alive. 
   • Personal protective equipment is indicated per standard precautions. 
   • If the skull is open or there is CSF leakage, line the body bag with materials to absorb any fluid and move the body in a sealed body bag. 
   • Label the toe tag with a "Special Processing Requirements" label before transport to the morgue. Labels are available from the Hospital Epidemiology Service. 
   • Contact the Admissions staff for issues regarding access to the morgue or for mortuary arrangements.
   • Keep the tissue separate from other biopsies or autopsy sections.
     
     
3. Processing the Tissues:
   

   • The intact brain is fixed in formalin for 1-2 weeks before cutting. 

   • Tissue blocks (representative regions of neocortex, basal ganglia, and cerebellum) are taken, agitated in at least 50-100 mL of 95-100% formic acid for one hour, and then returned to formalin for two days before embedding.
     Alternatively, one may take the necessary diagnostic sections from the fresh brain, fix them in formalin for 2-7 days, treat with formic acid for one hour, fix again in formalin for two days, and then embed in paraffin. This method significantly reduces infectivity.

4. Decontamination and Cleanup

   • At the conclusion of the autopsy, the area of incision and other contaminated skin surfaces are washed with freshly opened undiluted commercial household bleach (sodium hypochlorite). As sodium hypochlorite deteriorates after several months, a newly opened container should be used for each autopsy. After 10 minutes, the skin may be washed with water. All gowns, gloves, plastic sheets, and other disposable supplies are placed in a red or orange biohazard bag and incinerated. Alternatively, they may be autoclaved (132º C steam) and discarded. Hard surfaces are decontaminated with freshly opened undiluted bleach or NaOH. 1N NaOH is adequate unless there will be dilution by surface liquid, in which case 2N NaOH should be used. Bleach and NaOH are equally effective, but NaOH is preferred for steel instruments and surfaces because it is less corrosive than bleach. The disinfectant should remain in contact with the surface for at least 15 and preferably 60 minutes. Autopsy instruments should have any visible blood removed, then decontaminated with undiluted bleach or 1-2N NaOH as above. Alternatively, they may be autoclaved for one hour at 132º C and 20 psi (140 kPa).

   • Instruments are soaked in 2N NaOH for 60 minutes, then further cleaned as after non-CJD procedures.
   • Work surfaces are cleaned in 2N NaOH for 1 hour at room temperature. Please note that a 5- to 10-minute exposure of contaminated skin reportedly results in only minor irritation when washed thoroughly with water.
   • All tissue shavings from histology should be collected from around the microtome and disposed of by incineration.
   • The microtome blade and other working surfaces should be autoclaved or sterilized with 2N NaOH.
   • Unstained slides should be maintained in a protected environment, segregated from other material, and labeled with warnings for CJD.
     
     
5. Tissue for Confirmatory Diagnosis:
   • If Prion disease is suspected, the pathologist will collect tissue to be sent to the National Prion Center for confirmation.
   • Freeze 0.5 g of tissue for biochemical studies in a -70°C freeze until ready to ship. Ship in dry ice to the National Prion Center. Five grams (5g) of tissue is the ideal amount, but as little as 10 mg is sufficient.
   • The remaining tissue should be fixed in 10% buffered formalin for at least 24 hours followed by 1 hour formic acid (range of formic acid should be between 88-98%) and then by at least 24 hours of additional fixation in formalin. If fresh tissue is unavailable, the tissue extracted from melted paraffin block can be inactivated and sent for limited testing.
     
     
6. Notifications Required:
   • Primary Care Physician:  The individual responsible for notifying the patient’s family in non-NIH cases. If NIH Clinical Center patient, then the Clinical Center Epidemiology Department will notify the family.
   • LP physicians and technical staff having any involvement with the case.
   • NIH Clinical Center Occupational Medical Service (OMS).
   • NIH Clinical Center Epidemiology (complete an NIH Clinical Center Occurrence Report). LP manager will document notifications.
   • Funeral Home and Diener.
   • Maryland Department of Health and Mental Hygiene - this agency is responsible for notifying the Centers for Disease Control (CDC): 
     
     Montgomery County Office
     Telephone: 240-777-1755
     2000 Dennis Avenue, Suite 238
     Silver Spring, MD 20902

Useful Links:

• CDC’s Office of Health and Safety, Creutzfeldt-Jakob Disease (CJD) in Healthcare Settings

• CDC’s Infection Control Practices for CJD

• Maryland Public Health Reportable List 

• NIH Clinical Center ’s Occurrence Reporting System Website

• National Prion Disease Pathology Surveillance Center (NPDPSC)

• The World Health Organization Infection Control Guidelines for Transmissible Spongiform Encephalopathies

C. Cases with Bloodborne Pathogens (e.g., HIV, HTLV-I, hepatitis B, hepatitis C)

In addition to following Universal Precautions for these cases, we recommend the following:

• No tissue distribution to investigators, with the exception of those who are specifically studying the infectious agent in question (e.g., HIV).
• Notifying mortuary personnel by ensuring that this information is stated in the Report of Death Form.
• Avoiding frozen sections on these autopsy cases.
• Decontaminating instruments and working surfaces with a 10% solution of household bleach. (However, bleach is not to be directly added to the tissue sections to be taken for histology.)

1. Disposal of Tissue:

• Tissue is fixed in 10% formalin for 6-12 months before it is discarded. We follow the NIH Waste Management Guidelines for Disposal of Medical-Pathological Waste. Contaminated gloves and towels are treated in the same manner as tissue. A “discard” bucket containing formaldehyde is made available at all times for the decontamination of tissues, etc.

2. Labeling of Potentially Hazardous, Infectious Tissue:

• Cases requiring specialized precautions for infection control are on documentation (Death Report Forms) submitted to mortuary personnel. Cases with a history of Creutzfeldt-Jakob slow virus disease should be specifically labeled as such.

3. Infectious Aerosols/Formaldehyde Fumes:

• As much as possible, exposure to aerosols of infectious agents and toxic fumes are minimized by keeping tissues damp during dissections, appropriately stored in covered containers, and extensively washing them in water prior to presentation at conferences.

4. Employee Health:

1. 1. The autopsy assistants, residents, and other personnel that may come in contact with human tissues, blood, and/or potentially infectious materials are enrolled in a surveillance program provided by OMS. Screening for M. tuberculosis and hepatitis B exposure is provided. 
   2. The Report of Death Form (NIH Form 1082) has been modified to require notification in the case of known transmissible, infectious diseases or the presence of radioactive substances.
   3. All postmortem reports are made available to a nurse epidemiologist who reviews all the autopsy diagnoses searching for clinically unsuspected or undiagnosed infections detected at autopsy.
   4. All laboratory personnel handling potentially infectious human tissues are encouraged to participate in the hepatitis B (HBV) vaccination program that includes education, serological testing, and immunization. Individuals who are not immune from hepatitis B and who refuse HBV vaccination are required by OSHA standards to sign an informed declination.
   5. All employees with potential for exposure to blood/potentially infectious materials are required to have annual Universal Precautions Training, which is provided by the Hospital Epidemiology Service (HES). Records of training will be kept by the HES.
   6. Refer to the DOHS policy on Hazardous Chemicals or Biological Materials Spills (e.g. Blood Spills and Other Potentially Infectious Material) policy for further guidelines.

5. Supplies /Equipment Needed:

Notes:

• NIH Self Service store is located in Room B1N105, ext. 496-2051
• Equivalent supplies may be substituted

6. Procedure:

1. Don gloves and, if indicated, other personal protective equipment, before cleaning spills of blood or other potentially infectious material.
2. To clean a small spill (<20 ml): carefully remove visible material with paper towels or some other absorbent paper; apply a disinfectant solution (i.e., Dispatch®, a CHS-issued stabilized bleach solution). Alternatively, a freshly mixed (no older than 24 hours) 1:10 dilution of bleach (i.e., 1 part bleach to 9 parts water) may be used. The area should remain wet with disinfectant for 10 minutes. Contaminated sharp objects shall be disposed of in a puncture-resistant, leak-proof, closeable container that is color coded or labeled with a biohazard symbol; contaminated biohazardous material should be carefully disposed into a Medical Pathological Waste box.
3. To clean a large spill (= 20 ml): contact the Housekeeping and Fabric Care Department (6-2417). Prior to the arrival of housekeeping personnel, close the spill area to traffic. Do not cover the spill with paper towels and do not apply disinfectant (e.g., bleach, or Dispatch® ) or any other liquid cleaner to the spill. If desired, powder absorbent may be applied to spills on hard surfaces. Do not apply powder absorbent, bleach, or Dispatch® to spills on carpets.
4. When cleaning spills of blood or other potentially infectious material on hard surfaces, staff will: first, ensure that the spill has been appropriately contained; second, carefully remove visible blood, other potentially infectious material, or other organic material; third, sanitize the area through application of a CC-approved disinfectant to the spill area, keeping the area wet with disinfectant for 10 minutes.
5. Contaminated sharp objects shall be disposed of in a puncture-resistant, leak-proof, closeable container that is color coded or labeled with a biohazard symbol; contaminated biohazardous material should be carefully disposed into a Medical Pathological Waste box.
6. Blood or other potentially infectious body fluid contamination from patients on "CNS Precautions" may require special procedures. Refer to "CNS Precautions" or call the Hospital Epidemiology Service (HES) at 6-2209.

II. Cytology Service

1. Universal precautions as outlined by OSHA/NIH Clinical Center requirements are routinely utilized when preparing all specimens (i.e., gloves, lab coats, protective eye wear).
2. In addition to the above universal precautions, all sputum samples, bronchoalveolar lavages, washes and brushes, as well as any specimen from a patient in whom tuberculosis (TB) is suspected are prepared in a Class II laminar flow hood. Preparation in hood includes: opening of, pipetting, pouring or smearing of such sample before fixation (i.e., any manipulation of the sample that might create an aerosol). Cytospin samples are loaded and unloaded within the hood. In suspected TB cases, disposable, single use, capped sample chambers are employed. In addition to protective barriers noted in step 1 (see above), masks are required when handling such specimens.
3. All disposable items (i.e., pipets, filter cards and cuvetts) are placed in a bucket containing disinfectant vesphene for a minimum of 10 minutes to decontaminate before disposal.
4. The laminar flow hood, cytospin machine, centrifuge, and all bench tops are washed each day with a 10% chlorine bleach solution.
5. Any specimen from a suspected or known TB/MDR-TB, Respiratory-Isolation Level III patient, submitted to Cytology for evaluation of infection will be re-routed to the Microbiology Lab--Room 2C-385. If a malignancy is clinically suspected in a suspected or known TB/MDR-TB Respiratory-Isolation Level III patient, the specimen is fixed in 10% buffered formalin for a 24-hour period to de-activate the mycobacteria. This procedure is performed in a Class II hood with an equal amount of 10% buffered formalin added to the specimen following step 2 above
6. It is contraindicated to prepare slides for review on-site from a fine needle aspiration (FNA) on a suspected or known TB/MDR-TB, Respiratory-Isolation Level III patient without a Class II hood and proper fixation. When performing an FNA procedure, if a malignancy is to be ruled out the specimen is put directly into sterile, preservation-free normal saline and brought to Cytopathology for handling as per step 5. If infection is the primary concern, the sample should be sent to Microbiology (Room 2C385) for processing and evaluation.

III. Other Diagnostic Services

1. Procedures for other diagnostic services that require handling blood, human tissues, and potentially infectious materials (Surgical Pathology Service, Cytopathology Service, Hematopathology Service, Molecular Diagnostics, Chromosome Pathology, Tissue Procurement Facility) are comparable to those described above for the Autopsy Service. Barrier protection is required as noted above.
2. Tissues not utilized immediately for histological examination are fixed in 10% formalin and kept within the department for a minimum of 8 weeks. If the case has been signed out and if the tissues are no longer required, fixed tissues are disposed of according to  NIH Waste Management Guidelines for Disposal of Medical-Pathological Waste. Cells and/or potentially infectious materials may be autoclaved before disposal.