PATIENT PRESENTATION A 62-year-old Caucasian man developed multiple lesions on his trunk and extremities. He had acute myelogenous leukemia (AML) and had undergone a stem cell transplant 6 months earlier. When we examined him, we noted multiple, scattered vesicles on erythematous bases on his chest, back, arms and legs. WHAT’S YOUR DIAGNOSIS? Turn to page 63 for an answer and for more details about the condition and this case. MAKING THE DIAGNOSIS You can usually make the diagnosis of varicella zoster virus (VZV) infection based on a clinical examination. When your patient is immunocompromised, it’s even more essential to accurately make this diagnosis. The Tzanck preparation remains an excellent diagnostic tool for detecting VZV, although it can’t distinguish between herpes viruses. A multitude of tests exist, such as viral culture, serology, direct immunofluoresence and molecular techniques, in addition to routine histology. Viral culture provides specific identification of the virus; however, this is difficult as VZV is labile and difficult to culture.1 Direct immunofluorescence serves as an efficient means of viral identification. The use of molecular techniques such as polymerase chain reaction and hybridization utilizing viral-specific oligonucleotide and radioactive probes may also be utilized with a high degree of specificity. In this case, a Tzanck preparation revealed nu-merous multinucleated giant cells. High-dose acyclovir (10 mg/kg I.V. every 8 hours) was initiated, and he was placed in respiratory isolation. Multiple punch biopsies showed diffuse spongiosis with multinucleated keratinocytes and a diffuse superficial and deep inflammatory infiltrate. Viral cultures confirmed the diagnosis of VZV infection. He responded well to therapy and his lesions resolved within approximately 10 days. PATHOLOGY The histopathologic appearance of VZV cutaneous infection is similar to that of herpes simplex; however, there’s typically more vascular damage, microthrombi and hemorrhage in varicella. Characteristic features include cellular ballooning, reticular degeneration of the epidermis, acantholysis, multinucleated keratinocytes and nuclear chromatin marginization. TREATMENT Treatment of disseminated VZV in an immunocompromised host necessitates immediate diagnosis and action. In adults, development of varicella pneumonia carries a high mortality rate, up to 30% in immunocompromised patients.2 High-dose acyclovir (500 mg/m2 IV every 8 hours for 7-10 days) is the mainstay of therapy.3 Use caution in patients who have renal insufficiency and in elderly patients, as they may require a lower dose. Additionally, such patients should be placed in respiratory isolation. Unlike the immunocompetent host, immunocompromised hosts with disseminated VZV infection should remain in respiratory isolation for the duration of their hospital stay. Also, take care to identify hospital personnel who had been exposed to the patient. Administration of varicella-zoster immune globulin (VZIG) is indicated for post-exposure prophylaxis in susceptible immunocompromised patients.
Infectious or Non-infectious Etiology in This Immunocompromised Host?
PATIENT PRESENTATION A 62-year-old Caucasian man developed multiple lesions on his trunk and extremities. He had acute myelogenous leukemia (AML) and had undergone a stem cell transplant 6 months earlier. When we examined him, we noted multiple, scattered vesicles on erythematous bases on his chest, back, arms and legs. WHAT’S YOUR DIAGNOSIS? Turn to page 63 for an answer and for more details about the condition and this case. MAKING THE DIAGNOSIS You can usually make the diagnosis of varicella zoster virus (VZV) infection based on a clinical examination. When your patient is immunocompromised, it’s even more essential to accurately make this diagnosis. The Tzanck preparation remains an excellent diagnostic tool for detecting VZV, although it can’t distinguish between herpes viruses. A multitude of tests exist, such as viral culture, serology, direct immunofluoresence and molecular techniques, in addition to routine histology. Viral culture provides specific identification of the virus; however, this is difficult as VZV is labile and difficult to culture.1 Direct immunofluorescence serves as an efficient means of viral identification. The use of molecular techniques such as polymerase chain reaction and hybridization utilizing viral-specific oligonucleotide and radioactive probes may also be utilized with a high degree of specificity. In this case, a Tzanck preparation revealed nu-merous multinucleated giant cells. High-dose acyclovir (10 mg/kg I.V. every 8 hours) was initiated, and he was placed in respiratory isolation. Multiple punch biopsies showed diffuse spongiosis with multinucleated keratinocytes and a diffuse superficial and deep inflammatory infiltrate. Viral cultures confirmed the diagnosis of VZV infection. He responded well to therapy and his lesions resolved within approximately 10 days. PATHOLOGY The histopathologic appearance of VZV cutaneous infection is similar to that of herpes simplex; however, there’s typically more vascular damage, microthrombi and hemorrhage in varicella. Characteristic features include cellular ballooning, reticular degeneration of the epidermis, acantholysis, multinucleated keratinocytes and nuclear chromatin marginization. TREATMENT Treatment of disseminated VZV in an immunocompromised host necessitates immediate diagnosis and action. In adults, development of varicella pneumonia carries a high mortality rate, up to 30% in immunocompromised patients.2 High-dose acyclovir (500 mg/m2 IV every 8 hours for 7-10 days) is the mainstay of therapy.3 Use caution in patients who have renal insufficiency and in elderly patients, as they may require a lower dose. Additionally, such patients should be placed in respiratory isolation. Unlike the immunocompetent host, immunocompromised hosts with disseminated VZV infection should remain in respiratory isolation for the duration of their hospital stay. Also, take care to identify hospital personnel who had been exposed to the patient. Administration of varicella-zoster immune globulin (VZIG) is indicated for post-exposure prophylaxis in susceptible immunocompromised patients.
PATIENT PRESENTATION A 62-year-old Caucasian man developed multiple lesions on his trunk and extremities. He had acute myelogenous leukemia (AML) and had undergone a stem cell transplant 6 months earlier. When we examined him, we noted multiple, scattered vesicles on erythematous bases on his chest, back, arms and legs. WHAT’S YOUR DIAGNOSIS? Turn to page 63 for an answer and for more details about the condition and this case. MAKING THE DIAGNOSIS You can usually make the diagnosis of varicella zoster virus (VZV) infection based on a clinical examination. When your patient is immunocompromised, it’s even more essential to accurately make this diagnosis. The Tzanck preparation remains an excellent diagnostic tool for detecting VZV, although it can’t distinguish between herpes viruses. A multitude of tests exist, such as viral culture, serology, direct immunofluoresence and molecular techniques, in addition to routine histology. Viral culture provides specific identification of the virus; however, this is difficult as VZV is labile and difficult to culture.1 Direct immunofluorescence serves as an efficient means of viral identification. The use of molecular techniques such as polymerase chain reaction and hybridization utilizing viral-specific oligonucleotide and radioactive probes may also be utilized with a high degree of specificity. In this case, a Tzanck preparation revealed nu-merous multinucleated giant cells. High-dose acyclovir (10 mg/kg I.V. every 8 hours) was initiated, and he was placed in respiratory isolation. Multiple punch biopsies showed diffuse spongiosis with multinucleated keratinocytes and a diffuse superficial and deep inflammatory infiltrate. Viral cultures confirmed the diagnosis of VZV infection. He responded well to therapy and his lesions resolved within approximately 10 days. PATHOLOGY The histopathologic appearance of VZV cutaneous infection is similar to that of herpes simplex; however, there’s typically more vascular damage, microthrombi and hemorrhage in varicella. Characteristic features include cellular ballooning, reticular degeneration of the epidermis, acantholysis, multinucleated keratinocytes and nuclear chromatin marginization. TREATMENT Treatment of disseminated VZV in an immunocompromised host necessitates immediate diagnosis and action. In adults, development of varicella pneumonia carries a high mortality rate, up to 30% in immunocompromised patients.2 High-dose acyclovir (500 mg/m2 IV every 8 hours for 7-10 days) is the mainstay of therapy.3 Use caution in patients who have renal insufficiency and in elderly patients, as they may require a lower dose. Additionally, such patients should be placed in respiratory isolation. Unlike the immunocompetent host, immunocompromised hosts with disseminated VZV infection should remain in respiratory isolation for the duration of their hospital stay. Also, take care to identify hospital personnel who had been exposed to the patient. Administration of varicella-zoster immune globulin (VZIG) is indicated for post-exposure prophylaxis in susceptible immunocompromised patients.
