Early vs Late Congenital Syphilis

Early congenital syphilis :

• Non - immune hydrops
• Macerated skin 
• Thrombocytopenia

Late congenital syphilis :

• Hutchinson teeth
• Mulberry molars
• Saber shins

HSV Retinitis vs CMV Retinitis

Difference between HSV Retinitis and CMV Retinitis

Immunodeficiency Disorders - ( Easy way to Remember ) - USMLE

CVID :

B cells normal in numbers ; but decrease in IgG IgM and IgA

• Recurrent sinopulmonary infections in adults 
• Decreased response to Antigen stimulation of B cells .
• NORMAL amount of lymphoid tissues 

Rx : IV immunoglobulins

X-linked (Bruton) Agammaglobulinemia :

• Male Children 
• B cells and Lymphoid tissue are diminished 
• Absence of the tonsils, adenoids , lymph nodes . T cell NORMAL 

Rx : IVIG

SCID :

Combined so Both B and T cells - related to both : B cells : recurrent sinopulmonary infection as early 6 month. T cells : Candida , AIDS , PCP

Rx : BMT

IgA deficiency :

• sinopulmonary infections : Difference it also have Atopic diseases , Anaphylaxis to blood tranfusion when blood is given from a patient who has normal levels of IgA
• Sprue like condition with fat malabsorption 

Rx : infections and use blood from igA-deficient donors or that has been washed.

Hyper IgE: skin infections with staph.

CGD:

lymph nodes with purulent material leaking out . Abnormal NBT testing .

Lyme disease

Lyme disease.Erythema chronicum migrans. Expanding “bull’s eye” red rash.

Caused by Borrelia burgdorferi,which is transmitted by the tick Ixodes A (also vector for Babesia). Natural reservoir is the mouse.Mice are important to tick life cycle.

Common in northeastern United States.

Initial symptoms—erythema chronicum migrans, flu-like symptoms, +/- facial nerve palsy.
Later symptoms—monoarthritis (large joints) and migratory polyarthritis, cardiac (AV nodal block), neurologic (encephalopathy, facial nerve palsy, polyneuropathy).

Treatment: doxycycline, ceftriaxone.

mnemonic of Eosinophilia

mnemonic of Eosinophilia

Dengue fever and its prevention

Breakbone fever mosquito borne tropical disease ''Dengue Virus''

Symptoms :-

Febrile phase

• Sudden onset fever
• headache
• mouth and nose bleeding
• muscle and joint pains
• Vomiting
• rash
• diarrhea

Critical phase

• Hypotension
• pleural effusion
• ascites
• GI bleeding 

Recovery phase

• Altered level of consciousness
• seizures
• itching
• slow heart rate

Common symptoms :

1.Fever
2.Headache
3.Muscular and joint pain
4.Skin rash similar to measles

In small portion of cases :
Dengue hemorrhage fever resulting bleeding, low level of platelets

Rx:

Acute Condition: Supportive (paracetamol)  and Oral or IV rehydration

• Do not prescribe Aspirin , Ibuprofen and Antibiotics ( Contraindicated) 

For Severe Cases: IV fluids and blood transfusion

Prevention: No vaccine but get rid if open source of water.

Gram positive Cocci Classification

Polycistronic mRNA (Bacterial lac operon)

Bacterial mRNA can be polycistronic, meaning that one mRNA codes for several proteins. An example of polycistronic mRNA is the bacterial lac operon, which codes for the proteins necessary for lactose metabolism by E. coil; the transcription and translation of these bacterial proteins is regulated by a single promoter, operator, and set of regulatory elements. 

Opportunistic and Deep Mycoses

Coccidioides immitis  (Southwest USA)

• Located in desert soil
• Characteristic structures
• In the environment:  Arthroconidia
• In the body:  Sphereules are pathognomonic

Blastomyces dermatitidis  (north central and southeast USA)

• Associated with water

Lymphocutaneous Sporotrichosis

Mucocutaneous mycoses:  candida and dermatophytosis (get inflammatory response)

• Candida albicans
• Primary cutaneous candidiasis
• Mucocutaneous candidiasis

Candidiasis

• Wide range of infections
• Candida albicans is the most virulent species
• Candida spp. are common organisms of the skin, GI and UG tracts.
• Candidiasis is a disease of compromised hosts.

Mucocutaneous (T CELL IMPAIRMENT)

• Systems affected:
• GI tract, skin, vagina
• Onychomycosis
• Keratitis
• Symptoms:  Odynophagia, stridor, etc.
• Diagnosis: white pseudomembranous plaques with hyphae, pseudohyphae, and budding yeast.
• Groups at risk
• HIV patients
• Diabetics
• Pregnancy
• Age
• Antibiotics
• Steroids

Chronic mucocutaneous candidiasis – autoimmune polyendocrinopathy candidosis ectodermal dystrophy

• Inherited disorder of CMI to candida along with polyendocrinopathies
• Intractable candida infection of the mucocutaneous areas
• Concurrent adrenal insufficiency and hypoparathyroidism
• Type I diabetes
• Hypothryroidism
• Hypogonadism
• Ectodermal dystrophy

Deeply invasive candidiasis (think CANCER)

• Systems affected/ symptoms and signs:
• Candidemia
• Endocarditis – organism is sticky
• Hepatosplenomegaly
• Acute, shocklike syndrome
• Renal dysfunction

At risk groups:  

• Altered barriers
• Neutropenia
• Transplant
• Hemodialysis
• Pathogenesis
• Adherence and colonization
• Penetration through mucosal barriers and angioinvasions/access through catheters
• Hematogenous spread
• Replication yields necrosis +/- abscess with budding yeast and hyphae
• Look at the fundus!  Candida goes to the eyes!

Virulence factors of Candida

• Surface receptors
• Cell wall is an immune modulator
• Hydrolytic enzymes – e.g. acid protease, phospholipase
• Host mimicry – e.g. C3D receptor
• Dimorphism – makes it hardy!
• Germ tube + species.

Superficial:  

• Fungus confined to the stratum corneum or distal portions of hair
• Tinea versicolor:  Malassezia furfur
• Pigmentation changes due to fungal effect on melanocytes
• Can cause folliculitis
• Can cause fungemia in neonates with indwelling vascular catheters receiving total nutrition with lipids.
• Malassezia furfur is a lipophilic yeast and it requires fatty acids to grow.

Microscopic morphology of Aspergillus

Medical Mycology

• Microscopic morphology of Aspergillus fumigatus showing typical columnar, uniseriate conidial heads. Conidiophores are short, smooth-walled and have conical shaped terminal vesicles, which support a single row of phialides on the upper two thirds of the vesicle.

• Microscopic morphology of Aspergillus fumigatus showing typical columnar, uniseriate conidial heads. Conidiophores are short, smooth-walled and have conical shaped terminal vesicles, which support a single row of phialides on the upper two thirds of the vesicle.

• Microscopic morphology of Aspergillus niger showing large, globose, dark brown conidial heads, which become radiate, tending to split into several loose columns with age. Conidiophores are smooth-walled, hyaline or turning dark towards the vesicle. Conidial heads are biseriate with the phialides born on brown, often septate metulae. Conidia are globose to subglobose, dark brown to black and rough-walled 

• Microscopic morphology of Aspergillus flavus. Conidial heads are typically radiate, later splitting to form loose columns, biseriate but having some heads with phialides borne directly on the vesicle. Conidiophores are hyaline and coarsely roughened, often more noticeable near the vesicle. Conidia are globose to subglobose, pale green and conspicuously echinulate. Some strains produce brownish sclerotia. 

• Microscopic morphology of Aspergillus nidulans. Conidial heads are short columnar and biseriate. Conidiophores are usually short, brownish and smooth-walled. Conidia are globose and rough-walled.

• Grocott's methenamine silver GMS stained tissue section of lung showing fungal balls of hyphae of Aspergillus fumigatus in lung tissue, note conidial heads forming in an alveolus

• Grocott's methenamine silver GMS stained tissue section of lung showing fungal balls of hyphae of Aspergillus fumigatus

• Asperilloma found at post-mortem in the lung of a child with leukemia.  Note fungus ball occupying cavity