HIV and Opportunistic - THE REST

Question 1

Most common cause of CNS space occupying lesion in AIDS pts

Answer 1

Toxoplasmosis gondii

Question 2

Discuss the course of Toxoplasmosis

Answer 2

Cause: reactivation of latent cysts in tissues, infected meat/water, animal feces, cat litter boxes, transplacental transmission (if first time infection for mom)

Question 3

Discuss MRI findings for Toxoplasmosis

Answer 3

MRI: brain has multiple ring enhancing lesions

Question 4

Histology and Lab reports for Toxoplasmosis

Answer 4

Histo: necrotizing granulomas with thin capsule, cysts in muscles.

Labs: serology= (+) IgG toxoplasma antibody
Brain biopsy to differentiate from CNS lymphoma.

Question 5

Symptoms of Toxo

Answer 5

Sx: Sz, lethargy, AMS, localized weakness, encephalitis, Chorioretinitis.

Question 6

How do we treat Toxo

Answer 6

Tx: Sulfadiazene and pyrimethamine with a luecovorin rescue. Prophylacitc when IgG positive and CD4+

Question 7

Discuss the morphological and histological findings of Kaposi Sarcoma

Answer 7

KSHV virus causes (Herpes 8)

Gross: - Red-purple patches, macules, papules, plaques or nodules

Morph: - nodular, Sheets of plump, proliferating spindle cells

Dilated irregular endothelial cell-lined vascular spaces with interspersed lymphocytes, plasma cells, and macrophages

Question 8

Discuss the course of Kaposi Sarcoma

Answer 8

Likes lymphatic and vascular endothelium, mesenchymal stem cells, B cells, macrophages, and hops around via various receptors. It does not integrate, rather it stays episomal. During the latent infection it is not producing new progeny and has limited expression of virus genes.

During the lytic phase, it has many viral genes expressed and makes a lot of progeny.

Question 9

Labs for Kaposi Sarcoma

Answer 9

Lab:Confirm these spindle cells with IHC, positive for LANA (latent associated nuclear antigen)

Question 10

What genetic findings do we associate with Kaposi

Answer 10

1) LANA-1 - Inhibits p53, induces angiogenesis
2) vCyclin - induces entry to cell cycle by blocking cyclin D Kinase inhibitors
3) vFLIP - Inhibits apoptosis

Question 11

Treatment for Kaposi Sarcoma

Answer 11

Tx: excision,radiation,chemo Rx (good prognosis). Begin with ARTs (inhibit HIV to restore CD4 and CD8 counts). Advanced cases = Liposomal adriamycin is the favored agent for advanced KS in combination with modern cART

Question 12

Discuss the gross view and the histology we see with Bacillary Angiomatosis

Answer 12

Gross: non-blanching, Red papules or nodules in skin; similar to Kaposi’s

Histo: PMN inflammation & capillary proliferation
- Bacilli clusters (+) Warthin-Starry stain

Question 13

Discuss the signs of burkitt lymphoma

Answer 13

sx: extranodal masses
- Africa: endemic, jaw
- USA: sporadic, intestinal

Question 14

Treatment for Burkitt Lymphoma

Answer 14

tx: chemo, very responsive

Question 15

What is Hodgkin Lymphoma and what does it look like

Answer 15

neoplasms of large B cells: Reed-Sternberg cells (CD15 and CD30)

secretes cytokines

histo: multi-lobed “owl eyed” nuclei, inflamm and fibrosis

Question 16

Symptoms of Hodgkin Lymphoma

Answer 16

sx: fever, chills, weight loss, night sweats

localized to a single axial group of nodes (cervical, mediastinal, para-aortic)

Question 17

What is the worst type of Hodgkin Lymphoma that we see in HIV patients and how does it present

Answer 17

Lymphocyte depletion
worst prognosis; most aggressive

presents with advanced disease

Reticular variant:paucity of background reactive cells
most EBV+

Question 18

General review of Chorioretinitis and what can cause it

Answer 18

inflammation of the choroid (thin pigmented vascular coat of the eye) and retina (“posterior uveitis”)

sx: floating black spots, blurred vision, pain or redness in the eye, sensitivity to light, or excessive tearing

cause in Adults (*immunocompromised):

• viruses: HSV, VZV, CMV
• fungi: Candida, Aspergillus, Histoplasmosis, Fusarium
• protozoa: Toxoplasmosis (picture above)
• helminths: Toxocara canis
• bacteria: Mycobacteria tuberculosis

Question 19

What causes HIV thrombocytopenia

Answer 19

Impaired platelet production + increased destruction = thrombocytopenia, secondary to megakaryocytes (make platelets) having CD4 and CXCR4 receptors for HIV to find.

HIV also hyperproliferates B cells and dysregulates them leading to production of autoantibodies, many of which target platelets (glycoprotein IIb and II complexes on platelets) and Megakaryocytes (which are ALSO more prone to self-apoptosing = further destruction)